Chelsea were punished for a profligate showing at Borussia Dortmund after Karim Adeyemi's second-half strike secured a slender 1-0 lead in the Champions League last 16.
Graham Potter's side will have home advantage in the return match at Stamford Bridge on March 7 but left Signal Iduna Park ruing missed chances on Wednesday.
Joao Felix spurned a pair of glorious first-half opportunities in an entertaining encounter in Germany, before Adeyemi's 63rd-minute goal inflicted further misery on Chelsea after a ruthless counter-attack.
The Blues still have the chance to turn the tie on its head, but Potter and his men cannot afford similar struggles in front of goal in the second leg in west London.
Thiago Silva had the ball in the back of the net after 16 minutes, only to see the goal ruled out and the centre-back cautioned for a seemingly intentional handball past Gregor Kobel.
Chances continued to flow in a frenetic first half as Marius Wolf sliced a golden opportunity wide and Sebastien Haller fired narrowly off target from a presentable opening.
Joao Felix wastefully blazed over before hitting the crossbar after a driving run, while Wolf arrowed just wide with Kepa Arrizabalaga scrambling.
Kobel produced an expert stop to deny Reece James' pinpoint free-kick after the interval, before the Dortmund goalkeeper thwarted a bouncing volley from the England right-back soon after.
Adeyemi was clinical when Dortmund broke from the resulting corner, released by Raphael Guerreiro and powering past Enzo Fernandez before rounding Kepa to score.
Emre Can then cleared off the line after Kalidou Koulibaly's effort squirmed under Kobel, who kept Dortmund's narrow lead intact with a fine stop from Fernandez in the final minute.
What does it mean? Advantage Dortmund
Dortmund defeated an English side in European competition for the first time in 11 attempts, although their first such victory since March 2016 – against Tottenham – came with a degree of fortune.
Potter will wonder what his Chelsea side must do to get past Kobel in the return meeting after Joao Felix's pair of misses came back to haunt the Blues on the road.
A repeat performance at home may be enough to down Dortmund, but Potter's men cannot bank on having such a plethora of chances again as they stare down the barrel of an early European exit.
Adeyemi the difference
While the brilliant Brandt created four chances in a productive display, Adeyemi will steal the headlines for his remarkable goal on the break.
The 21-year-old has scored in each of his last three competitive appearances – one more than in his first 20 games for BVB.
Havertz's Dortmund wait goes on
Kai Havertz has repeatedly been trusted by Potter to lead Chelsea's line, but the Germany international suffered a familiar fate against BVB.
The forward managed to create four chances and also attempted four shots, but he has now played eight games against Dortmund without scoring – more than against any other opponent in his club career. He has lost all five away games against Dortmund.
What's next?
Chelsea return to Premier League action at home to Southampton on Saturday, while Dortmund host Hertha Berlin the following day in the Bundesliga.
Inter 2-0 Torino: Nerazzurri ease to win in party atmosphere
Hakan Calhanoglu scored twice to give newly-crowned Serie A champions Inter a comfortable 2-0 win over 10-man Torino on Sunday, extending their unbeaten league run to 28 games.
It was a party atmosphere at the San Siro with confetti and fireworks before kick-off as the Inter fans continued to celebrate the Scudetto title they secured on Monday with a 2-1 derby win over Milan.
Inter's win over Torino moves them onto 89 points, 19 clear of Milan with four games remaining.
The Torino players gave Inter a guard of honour as they entered the pitch and Inter coach Simone Inzaghi answered the crowd's call for him to celebrate with them.
In the first Serie A game to be officiated by an all-female refereeing team, four minutes after half-time Maria Sole Ferrieri Caputi sent off Torino's Adrien Tameze for a foul on Henrikh Mkhitaryan.
Inter made the breakthrough seven minutes later when Mkhitaryan passed to Calhanoglu in the area who drove a shot into the bottom corner.
Calhanoglu converted a penalty four minutes later after a foul on Marcus Thuram and the party will continue into the evening as the Inter players parade through the streets of Milan on open-top buses.
Torino remain 10th in the standings on 46 points.
St. Mirren 1-2 Rangers: Dessers nets winner as Gers keep touch on Celtic
Rangers boosted their Scottish Premiership title hopes as Cyriel Dessers' strike earned a narrow 2-1 win over St. Mirren at the SMISA Stadium on Sunday.
Rangers were ahead with 32 minutes played as Zach Hemming failed to deal with a cross before James Bolton inadvertently put through his own net under pressure from Dessers.
But St. Mirren hit back just five minutes later as Mikael Mandron nodded goalwards, with the ball flying just past the fingertips of Jack Butland before going in off the post to send the teams into the break level.
Rangers needed a response in the second half, and they got exactly that with 18 minutes left to play as Dessers was left with far too much space in the middle to head James Tavernier's cross into the back of the net.
The hosts huffed and puffed for another equaliser but ultimately could not find one as Rangers held on for three much-needed points that move them level with leaders Celtic but with an inferior goal difference, leaving them second ahead of Celtic's visit to Dundee later on Sunday.
St. Mirren, meanwhile, remain fifth in the Scottish Premiership table.
Al-Khaleej 0-1 Al-Nassr: Ronaldo misfires on return as Laporte nets winner
Cristiano Ronaldo returned from suspension but failed to find the net as Al-Nassr secured a 1-0 win over Al-Khaleej on Saturday, with Aymeric Laporte coming up with the decisive goal.
Ronaldo was in action for the first time since being sent off for an elbow in a 2-1 Saudi Super Cup loss to Al-Hilal earlier this month, with his initial two-match ban being reduced to one on appeal.
He missed three good chances as Al-Nassr threatened to fall further behind runaway Saudi Pro League leaders Al-Hilal, but former Manchester City defender Laporte spared his blushes by nodding Marcelo Brozovic's deep free-kick into the bottom-left corner with 68 minutes gone.
Al-Nassr remain nine points adrift of Al-Hilal at the summit in spite of their win, with Jorge Jesus' team unbeaten through 28 games this season as they close in on a record-extending 18th title.
Data Debrief: Ronaldo misfires on return
Ronaldo was presented with the Saudi Pro League's Player of the Month award for March ahead of kick-off, having scored four goals in three league appearances last month.
However, his sights were off on Saturday as he failed to net despite three of the visitors' four big chances, as defined by Opta, falling his way. He led all players on the pitch for expected goals (1.27 xG), shots (five), shots on target (three) and touches in the area (nine) without reward.
SportsMax is the Caribbean sports channel of choice, committed to providing sporting content of the highest quality to the Caribbean, delivered by a team of highly innovative, passionate and qualified professionals.
(876) 619-7629
digitalmedia@sportsmax.tv
