Lionel Scaloni says he is "not here to criticise his players" after they suffered a shock 2-1 defeat to Paraguay in World Cup qualifying.

Lautaro Martinez had given Argentina the lead in the 11th minute – his powerful shot past Roberto Fernandez was initially ruled out for offside before a VAR review overturned it.

However, Paraguay were soon back on level terms. Gustavo Gomez rattled the crossbar with a diving header from a corner, but they regathered possession and pulled level with a sublime overhead kick from Antonio Sanabria 19 minutes in.

Two minutes into the second half, the hosts completed the turnaround through Omar Alderete, who met Diego Gomez's precise free-kick to nod in from close range.

Rodrigo De Paul arguably should have equalised for Argentina with just over 20 minutes to go, but under pressure, sliced over from close range, with the visitors unable to salvage a point.

It was a third defeat in World Cup qualifying for the Albiceleste, who remain top of the standings with 22 points, and Scaloni chose to focus on the positives.

"I'm not here to criticise my players; I'm here to support them," Scaloni said. "We knew it was going to be a tough match. We're here to move forward.

"In the first half, we played a good game, but the first action at the start of the second half made everything more difficult. We have to congratulate the opponent, who defended very well.

"I don't know if they found the antidote [to beating Argentina]. We're hoping to get back on the positive path.

"The team always tries and stands tall. That's what's important: never giving up on the game and always having the desire to compete."

Paraguay are sixth in the table, having extended their unbeaten run to six matches, which also includes a win over Brazil.

They had to dig deep, having only 23.2% possession throughout the game, though they had eight shots to Argentina's nine and scored with both of their efforts on target.

Head coach Gustavo Alfaro is yet to lose a game since taking over Paraguay after the Copa America, and he hailed his team's resilience.

"With the rebelliousness of these players in the face of adversity, I have no doubt that we will get there. When the predisposition is so great, time is secondary," he said.

"They were fantastic points, very difficult. It is difficult to take a point from Argentina."

Gustavo Alfaro has resigned as Costa Rica head coach after just nine months in charge.

The Argentine's exit was confirmed on Friday with speculation linking Alfaro as a potential successor to Daniel Garnero as Paraguay boss.

"We thank Mr Gustavo and his team for their dedication during their time leading the Costa Rica team," the Costa Rican Football Federation (FCRF) said in a short statement.

"At FCRF we will continue to build the path towards the 2026 World Cup. We will keep our fans informed and we reiterate our commitment to continue working for the development and success of national football."

The 61-year-old, who took charge of Ecuador at the 2022 World Cup, guided Costa Rice to the Copa America this year as his side were eliminated in the group stage by finishing third.

Ecuador head coach Felix Sanchez has said it is an honour to face Lionel Scaloni's Argentina ahead of their Copa America quarter-final on Friday. 

Sanchez, looking to secure Ecuador's first victory over Argentina since October 2015, praised his opposite number for his role in their 2021 Copa America and 2022 World Cup successes. 

"Scaloni has built something with which he has made history," Sanchez said. 

"It's a team that, as a spectator, is great to watch. It is an honour to be able to play against a team of this level."

Argentina are expected to be without captain Lionel Messi for the fixture at the NRG Stadium after sustaining a hamstring injury in their 1-0 win over Chile. 

However, Sanchez insisted that his side will still face a tough task despite the absence of Argentina's all-time leading goalscorer. 

"Obviously, he is a player who makes a difference," Sanchez said. "We have played against them with him and without him.

"The way they play does not change because they have managed to create a solid group and a very defined playing style that can be tweaked depending on the situation.

"We have to be prepared for any possibility and, based on that, adjust."

Sanchez, who took over from Gustavo Alfaro in March last year, has faced La Albiceleste on two occasions, losing both 1-0. 

Asked if he would do anything different this time around, he said: "We have to try to compete in the best way against a team that is difficult to score goals against.

"They are very solid and have many offensive variables.

"Something has to be changed to try to go toe to toe with them. Our last few matches against Argentina have been closely fought encounters.

"But now we know that we have to win to advance and our aim is to give ourselves every chance to do that." 

Aliou Cisse paid tribute to the absent Sadio Mane after Senegal booked their World Cup last-16 spot with a 2-1 win over Ecuador on Tuesday.

The Lions of Teranga leapfrogged their opponents into second in Group A as goals from Ismaila Sarr and Kalidou Koulibaly sealed their progression to the knockout stage for the first time since 2002.

The result also saw Senegal become the first African nation to beat a South American side at the World Cup since Cameroon overcame Colombia in 1990, ending a 21-game winless run.

Senegal's talisman Mane was ruled out of Qatar 2022 after suffering a leg injury for Bayern Munich in the build-up to the tournament, but Cisse's thoughts quickly turned to the forward in the aftermath of his side's huge win. 

"I would like to dedicate this victory to a man who is doing extraordinary things for the country, who is unfortunately not here today. This man is called Sadio Mane," he said.

Senegal face the winner of Group B on Sunday, and Cisse says his side will be well-prepared for any opponent.

"We don't know who we're going to come up against in the round of 16 – it could be England, it could be Wales, Iran, USA, anyone," Cisse added.

"Then that will be a new stage for us. We know that we are moving to the knockout stage, which is completely different from what we are used to playing in these types of [group] matches.

"Everyone is a good team, the best teams in the world that are competing. Therefore, we need to be prepared to come up against any side.

"It is now a win or lose situation, there are no second chances – if you win, you go through, if you lose, you go home.

"So for the moment, we are just going to concentrate on resting and getting fit for the next game, it is simple as that."

Ecuador head coach Gustavo Alfaro lamented the fine margins that saw his side miss out on the last 16 and confirmed he needs some time to decide whether he will remain in the job.

"The margin of error was meagre and small details made the difference," he said after seeing Moises Caicedo's second-half equaliser followed by Koulibaly's winner just moments later.

"We made key mistakes in the game. The pain of this defeat does not need to overshadow the achievements of this side, and we hope the experience serves them well in the future."

Asked about his own position, the Argentine added: "I need time to know what I am going to do with my professional career."

Gustavo Alfaro says Enner Valencia will be fit to face Netherlands after the Ecuador captain inspired a 2-0 win over Qatar in the first game of the World Cup.

Valencia became Ecuador's record World Cup goalscorer with five courtesy of a first-half double in a one-sided Group A opener against the hosts on Sunday.

The striker had an early goal contentiously disallowed by the VAR at Al Bayt Stadium before opening the scoring from the penalty spot after he was brought down by Qatar goalkeeper Saad Al Sheeb.

Ecuador's leading all-time goalscorer found the back of the net again with a powerful header as La Tri dominated the game in Al Khor.

There was concern when Valencia sustained a knee injury late in the first half and although he was able to continue, the skipper was withdrawn 15 minutes from time.

Ecuador head coach Alfaro allayed concerns over the 33-year-old's condition ahead of the clash with the Oranje at Khalifa International Stadium in Ar-Rayyan on Friday and praised the captain for silencing his critics.

"He is the all-time top scorer for Ecuador, he is going through tough times, he was questioned at times in Ecuador," said Alfaro.

"He managed to score, which means a lot to him. Four or five players took a few blows, but nothing serious.

"Enner will play against the Netherlands, there is no doubt about that."

Qatar were devoid of ideas, failing to register a shot on target as they became the first host nation to lose an opening match of a World Cup.

Felix Sanchez, the Qatar boss, knows they must go back to the drawing board before taking on Senegal on Friday after they were outplayed in their first ever World Cup match.

The Spaniard said: "We fought this game in a certain way, but our opponent had their own ideas. It's not that we didn't want to attack, but our opponent head their own weapons.

"If we want to be competitive, we will need to defend, and be very well organised. When we have possession of the ball we would like to be more effective.

"We will try to help our players and see if we can progress in all these aspects."

Ecuador coach Gustavo Alfaro says the absent Byron Castillo "will be with us" in an emotional sense after a controversial nationality dispute led to the defender not going to the World Cup.

Castillo was the subject of a complaint made by Chile in May, with the Chilean Football Federation alleging he was born in Colombia rather than Ecuador.

The case initially put Ecuador's World Cup qualification in doubt until the FIFA investigation was closed in June, and FIFA's Appeal Committee confirmed no further action was being taken three months later.

Chile appealed to the Court of Arbitration for Sport (CAS), who acknowledged Castillo's birthplace as being in Colombia, but the claim was dismissed on the basis of Ecuador legally recognising the player as Ecuadorian.

Nevertheless, Ecuador were still hit with a three-point deduction for the next World Cup qualification campaign for using a "document containing false information", and Alfaro was made to leave Castillo out of his squad for the World Cup as the Ecuadorian Football Federation (FEF) wanted to avoid "further unfair sanctions".

Speaking ahead of Sunday's clash with host nation Qatar, the opening game of the 2022 World Cup, Alfaro said: "I gave my opinion. He should be here, that's my opinion.

"I expressed my opinion about the CAS decision. I'm head coach, not a lawyer, I expressed an opinion, I talked to lawyers.

"I respect the decisions [of the Federation]. Byron should be here, but I respect the decision. We'll wait to see if they clarify why the three points [deduction] in the next qualifying stage, but the World Cup started in October. If he's ineligible for the World Cup, then he was [ineligible] for [October]. Ecuador is always facing hardship.

"We didn't cap him while the investigation was open. But after two sentences that said Byron was Ecuadorian, we did cap him.

"If you had only seen the pain Byron has had to endure…the love from the squad to Byron, he's now our symbol, and he'll be with us on the pitch even if he's not with us [physically]."

While there was undoubted sadness in Alfaro's voice as he discussed Castillo's situation, he otherwise spoke with great pride on Saturday as Ecuador prepare to take part in the World Cup's opening act.

He allowed himself a moment to reflect on his own history and the World Cup exploits of his Argentinian compatriots in the past, specifically Carlos Bilardo and Cesar Luis Menotti, winners in 1986 and 1978 respectively.

"First of all, as an Argentinian national, a coach, it fills us with pride [to work at a World Cup]," he continued. "In Argentina, the coaches all make a great effort to be professionals and reach this level, especially coaches like me who've had to work from the bottom up.

"I coached in the lower divisions and have a broad experience with different teams. Now this is my first national team [job] and World Cup. Looking back, there are so many famous Argentinian coaches who acted as beacons.

"Myself, Lionel [Scaloni, Argentina coach], Tata Martino [Mexico coach], we want to continue that legacy. It's up to us to represent Argentinian coaches now.

"Many have been in this position before. It's a great privilege for me to be part of that exclusive list of coaches at a World Cup, but on the other hand there aren't that many of us who've been able to coach our team in the opening game.

"Today, I feel very proud to come from Rafaela, to have been part of regional football in Argentina, and also the top division.

"I dreamed of being a coach there when everything felt so hard. I overcame many challenges and hurdles.

"I was told I wasn't good enough, wasn't up to the expectations, but when we dream we are able to achieve, I now have the privilege of being here talking to you."

Despite making history in Argentina's 1-1 draw against Ecuador, manager Lionel Scaloni seemed disappointed to share the points away from home.

It looked like it was going to be a win and a clean sheet for the visiting side after Julian Alvarez put them up in the first half, before late drama.

VAR ruled that a 90th-minute header struck the arm of an Argentinian defender, and Enner Valencia stepped up from the penalty spot and put home the rebound after his initial strike was saved.

With the result, Argentina have now played 31 games since their last loss, dating back to the 2019 Copa America semi-final, which is the longest active unbeaten run in international football.

Argentina's 31-game unbeaten streak also matched the record feat achieved by the national team from 1991 to 1993.

However Scaloni, who received a yellow card from the sideline, was focused on the difficulty of the World Cup qualifying campaign as a whole.

"These two dates [against Venezuela and Ecuador] were very hard for us," he told reporters.

"Between suspensions, injuries and players who arrived very fair, we had to support each other and I appreciate that very much. 

"They are very hard to play – sometimes people really don't realise how hard they are. I was just talking to the boys from the under-20s who came to watch the match, and they couldn't understand the degree of difficulty that the matches present.

"Today's game was played on a field that was not in good condition – it was almost impossible to play from below – even so, we had a good first half, but in the second they came to us."

It was a different story for Ecuador manager Gustavo Alfaro, who addressed the crowd and called it "one of the happiest moments of my life".

"I thank my family, everyone who was part of this process and this achievement, which is the most important in my career," he said.

"I am living one of the happiest moments of my life. Nobody believed in Ecuador, and today it stands up and says present to the world.

"The challenge that is coming to us [the World Cup] is for 17 million people."