Mallory Swanson marked her 100th cap with the winning goal as the United States defeated Brazil 1-0 to win a record-extending fifth Olympic gold medal in women's football.

Two-time runners-up Brazil were seeking their first gold and thought they had taken the lead early on at the Parc des Princes, only for Ludmila's strike to be rightly ruled out for offside.

Swanson used her pace to break clear soon after but was unable to get the better of Lorena, with neither side truly going close to finding a breakthrough in the first half.

The Selecao suffered a blow early in the second period when Vitoria Yaya was forced off the field on a stretcher and their outing soon got worse when Swanson fired home.

Chicago Red Stars forward Swanson held her line well, latched on to Korbin Albert's throughball and calmly slotted past Lorena with 57 minutes on the clock in Paris.

Brazil could have taken a game of few clear-cut chances to extra-time, but an unmarked Adriana saw her header kept out by Alyssa Naeher in stoppage time as Emma Hayes' team claimed gold.

Data Debrief: Swanson the golden girl for USA

Swanson was denied a dramatic goal on her 99th cap for the USA in their 1-0 extra-time win over Mexico in the semis, but she marked her century in the perfect manner as she scored for the fourth time this tournament.

The 26-year-old is the 44th player in USWNT history to reach that milestone and is the youngest since Amy Rodriguez (25) did so in 2012.

The USA's fifth Olympic gold, coming 12 years after their last success in London, takes them four clear of Germany, Canada and Norway as comfortably the most successful side in the competition.

Brazil cruised into the final of the Olympic Games with a 4-2 victory over Spain at the Orange Velodrome on Tuesday.

Salma Paralluelo netted two late consolations, but the damage was already done as Irena Paredes' own goal, Gabi Portilho, Adriana and Kerolin denied the world champions a place in the gold-medal match.

Brazil were still without legend Marta after she lost her appeal over a two-game ban, but her team-mates ensured she would bow out of Olympics action with the chance to play for the top prize.

Spain were behind after just six minutes as Cata Coll's poor clearance struck the unfortunate Paredes on the side to send it cannoning over the line.

La Roja struggled to gain a foothold, and Brazil doubled their advantage on the stroke of half-time thanks to Portilho's composure when one-on-one with Coll.

Adriana made sure of their progress off the bench in the 71st minute – she struck the bar but was then on hand to head Portilho's nod-down in from close range.

That sparked Spain into life and Paralluelo's looping header snuck in at the far post before Alexia Putellas rattled the crossbar and forced Lorena into a smart stop to slow down the comeback attempts.

Kerolin delivered the hammer blow in the opening seconds of stoppage time by sliding her low shot through Coll's legs, though Paralluelo would have the last say, poking in her second of the match from close range in the 112th minute. 

Data Debrief: World champions denied

Spain were aiming to become the first side to win Olympic gold after lifting the Women's World Cup, but they just fell short at the final hurdle after being outplayed.

La Roja's late flurry of chances meant they finished with more shots than Brazil (26 to their 17) and more on target (11 compared to seven).

Brazil's dominance showed in other ways though, as they created an expected goals (xG) of 3.27 and had a total of six big chances, as they secured a meeting with the United States in the final on Saturday.

Though slighted disappointed with the outcome of their opening loss to Brazil, Jamaica’s Head coach Hubert Busby took heart from aspects of his senior Reggae Girlz performance, which he is hoping they can build on to prove even more competitive in the second contest on Tuesday.

Out for the first time together in almost nine months, the core group of players that held Brazil to a goalless stalemate at last year's FIFA Women's World Cup, expectedly lacked cohesiveness and were simply outclassed by the South Americans, who romped to a 4-0 win in Saturday’s first encounter at the Arena de Pernambuco in Recife.

The iconic Marta led her team with a brace in the 64th and 90th minutes, while Adriana (26th), and a 38th-minute own-goal by Chantelle Swaby, propelled Brazil to a comfortable win.

However, with the proverbial rust now shaken, Busby, who didn’t have experienced defender Allyson Swaby and winger Jody Brown available for the first game, is anticipating a more fluid showing in the second encounter, with or without the duo as uncertainty surrounds their fitness for the decisive contest at the Fonte Nova Arena in Salvador.

Kickoff is 5:00pm Jamaica time.

Among the positives from the first contest was the fact that the Girlz did manage to show glimpses of their attacking prowess and even got the ball in the net from a corner early on, but it was ruled out for a foul, as Kayla McKenna nudged Brazil's custodian in an aerial challenge for possession. Besides that, only stand-in captain Deneisha Blackwood and goalkeeper Rebecca Spencer really showed any real fight in Jamaica's backline.

“Heading into the game, we’re looking to improve on all aspects of the game, and more importantly not just the result, which is the most important thing, but really look to improve our overall team performance,” Busby said in a pre-game interview.

“Allyson and Jody will be a little bit of game time decisions. Obviously, both players trained (on Monday), which is a positive sign, so we'll check in on them and decide where we go from there. It's important that we're not risking them because some of these players are getting ready to go into preseason, so their health and safety and overall well-being is important. So while we would love to have them as we seek to build on the positives of the first game, we won’t risk it if they are not ready,” he added.

As he reflected on, and assessed Saturday’s defeat, Busby again stressed the importance of ball possession, particularly when absorbing pressure defensively, and pointed to that as one element of their game in which he is expecting mark improvements.

“Football is a game of rhythm and moments, and we were never quite able to get into our rhythm or moments because we're always defending, and so one of the things we really need to work on going forward is our ability to hold up the ball up front and allow for us to get out as a group,” Busby reasoned.

“Once we do that, then we can then obviously look to attack a little bit more in numbers, which is something that is a part of our playing model and some of the principles that we try to implement. So we just need to rekindle the team’s understanding and chemistry and just build on that going forward,” he ended.