Alex Brotherton
BBC Sport journalist

Greece midfielder Konstantinos Karetsas had to leave the pitch with "circulatory problems" during Dortmund's Champions League win against Villarreal.

The 18-year-old, capped 10 times by his country, was substituted in the 27th minute after receiving treatment having slumped to the ground after playing a pass.

"Konstantinos Karetsas had to leave the field due to circulatory problems," said Dortmund in a statement. "Kosta is doing well under the circumstances and is on his way to the hospital for further tests."

Serhou Guirassy scored twice and netted an own goal as Borussia Dortmund opened their European campaign with a victory.

A Renato Veiga own goal gave hosts Dortmund the lead early in the second half, but Santiago Mourino drew Villarreal level after his side missed several opportunities.

Dortmund improved and Guirassy restored their lead in the 80th minute, before the Guinean striker converted a late penalty and then scored an own goal.

Villarreal failed to score in any of their four away matches in the Champions League last season. That curse looked set to continue as Georges Mikautadze scuffed a glorious chance from close range and Tajon Buchanan forced Gregor Kobel into a smart save.

Dortmund were fortunate to go into the break level, and in the 53rd minute were gifted the lead when Veiga inadvertently deflected a Maximilian Beier cross past his own goalkeeper.

But 14 minutes later Mourino caught out Kobel with a flicked near-post header, seconds after the Dortmund goalkeeper had received treatment.

Kobel made amends a minute later by tipping a fierce Buchanan strike over the crossbar, before Guirassy and Beier got in each other's way attempting to convert from a Marcel Sabitzer cross.

Guirassy's 100th Dortmund appearance had been a frustrating one, but he finally got his goal in the 80th minute when he tapped in from a Fabio Silva ball across the face of goal.

Since the start of 2024-25, Guirassy has been directly involved in 26 goals in 25 Champions League appearances, a record bettered only by Erling Haaland.

Guirassy scored his 64th Dortmund goal three minutes later from the penalty spot after he was fouled at a corner by Mourino.

Villarreal were given late hope when a Kobel save bounced back into the goal off Guirassy's face, and almost equalised in the fifth minute of injury-time when Veiga's close range effort was deflected wide.

Player of the match

E. Nwaneri
8.56
18 E. Nwaneri
8.56
7 J. Bellingham
7.50
9 S. Guirassy
7.17
14 M. Beier
7.08
1 G. Kobel
7.00
17 C. Chukwuemeka
7.00
22 J. Gadou
6.69
20 M. Sabitzer
6.64
26 J. Ryerson
6.55
8 F. Nmecha
6.50
24 D. Svensson
6.38
3 W. Anton
6.29
25 J. Veerman
6.27
19 K. Karetsas
6.25
36 Kauã Prates
6.10
21 Fábio Silva
5.80
Back to team tabs

After the opportunity to rate players has closed, the score displayed represents the average from all the submissions by BBC Sport users.

Watch highlights of every Champions League game from 22:00 on Wednesday on BBC iPlayer and the BBC Sport website and app.

There will also be a Champions League Match of the Day on BBC One on Wednesday, from 22:40 to 00:00.