Dortmund's English midfielder Jude Bellingham (center) outruns Chelsea's Croatian midfielder Mateo Kovacic (right) during the UEFA Champions League round of 16 second-leg football match between Chelsea and Borrusia Dortmund at Stamford Bridge in London on March 7, 2023. (PHOTO / AFP)

LONDON - Chelsea reached the Champions League quarter-finals as a first-half goal from Raheem Sterling and a controversial penalty by Kai Havertz overturned a first-leg deficit on Tuesday and propelled them to a 2-1 aggregate win over Borussia Dortmund.

Just as they had in Germany three weeks ago when Dortmund won 1-0, 2021 champions Chelsea squandered chance after chance in the first half, with Germany's Havertz hitting the post as well as the side netting.

Portugal loanee Joao Felix and defender Kalidou Koulibaly also went close and Sterling had efforts blocked.

But in the 43rd minute Ben Chilwell crossed into the box and found England team mate Sterling.

Sterling airkicked his first effort, then sidestepped Marco Reus and sent his second high into the net to put the teams level on aggregate.

Dortmund's Emre Can tries to control the ball during the Champions League round of 16 second leg soccer match between Chelsea FC and Borussia Dortmund at Stamford Bridge, London, on March 7, 2023. (PHOTO / AP)

It was Dortmund's first defeat following wins in their previous 10 matches and a boost for Chelsea, who have struggled for form under Graham Potter since the turn of the year, dropping to 10th place in the Premier League and losing early in their two domestic cups

"It was a massive performance," Sterling told BT Sport. "We had to dig deep. We took our chances. We felt as a team we could do it. "I had a little mis-kick with the first touch but it landed perfectly and allowed us to build on that for our performance."

Early in the second half a Chilwell cross smacked into the outstretched hand of defender Marius Wolf and Dutch referee Danny Makkelie gave the penalty after being called to the VAR screen. Havertz, taking over as penalty taker from Jorginho who moved to Arsenal in January, hit the keeper's left-hand post to the relief of the visitors.

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The game resumed for a few seconds until VAR alerted Makkelie that Dortmund players had encroached into the area.

Havertz retook the kick and sent the ball the same way but this time it squeezed inside the post to put Chelsea ahead in the tie in the 53rd minute.

"I don't know what I was thinking (when it hit the post) but the referee let me retake the penalty," Havertz said. "I was a bit nervous but I scored. I tried to wait and look at the keeper and the second one was a bit easier."

Chelsea's German midfielder Kai Havertz celebrates scoring the team's second goal from the penalty spot, after re-taking his first missed penalty, following a VAR review, during the UEFA Champions League round of 16 second-leg football match between Chelsea and Borrusia Dortmund at Stamford Bridge in London on March 7, 2023. (PHOTO / AFP)

We have been through a tough period and this competition means a lot for us. We wanted to progress and get into the last eight and it sets us up for the next few weeks.

Graham Potter, Chelsea head coach

It was Dortmund's first defeat following wins in their previous 10 matches and a boost for Chelsea, who have struggled for form under Graham Potter since the turn of the year, dropping to 10th place in the Premier League and losing early in their two domestic cups.

A smiling Potter punched the air and applauded the crowd as his team acknowledged the cheers.

"There was a fantastic feeling in the dressing room," he said. "We have been through a tough period and this competition means a lot for us. We wanted to progress and get into the last eight and it sets us up for the next few weeks."

He said he had confidence in Havertz to score but was too nervous to watch.

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"I wasn't watching it but delighted when I heard the roar.

"Taking penalties is not for me, so I am in awe of anybody (who does)."