(CNN) It's been quite a week for eight-time Olympic gold medalist Usain Bolt as he rub shoulders with some of the world's best football coaches and players.
On Thursday and Friday the fastest man in history was strutting his stuff kitted out in the famous yellow and black colors of German club Borussia Dortmund.
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The 31-year-old has long expressed an interest in playing football after retiring from sprinting.
Bolt trained alongside Marco Reus and Mario Gotze during the sessions and the Jamaican shared several photos on Instagram of his time with the Dortmund stars.
The Jamaican told reporters Dortmund were incredibly welcoming and that it was "overwhelming" to train in a stadium that can hold up to 81,000 people.
"I have to give them thanks for giving me this opportunity to come out and try to accomplish my new goals."
Bolt is keen to know how far he can take his football ambitions.
"I've talked to the club and told them I'm really serious about this so they said I should come back for a longer period and do some more training, then they can assess me and tell me what level I can play at.
"So I'm looking forward to that and that's my focus right now."
Friday's training session was broadcast live on Dortmund's social media channels.
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His Dortmund adventure comes after Bolt played in an all-star five-a-side friendly match in Basel, Switzerland in the Match of Friendship game on Wednesday, when he was coached by Manchester United boss Jose Mourinho.
"Usain has a double meaning for me -- it's the meaning of what he represents in the history of sports and also what he represents in the history of humanity," Mourinho told CNN Sport of his experience of working with Bolt.
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Bolt will next play at United's Old Trafford stadium in UNICEF's Soccer Aid match in June against Robbie Williams, along with other celebrity and football stars.
Back in 2016, former Dortmund star Pierre-Emerick Aubameyang, who left the Bundesliga club to join English Premier League side Arsenal in the January transfer window, challenged Bolt to a 30-meter sprint showdown.
"I'm waiting for you man," Aubameyang told Bolt during a CNN Sport interview. "I hope to see you one day, and let's do this challenge!"
In 2013, Gabon international Aubameyang clocked 3.7 seconds in a 30-m training run -- eight hundredths of a second faster than Bolt over the same distance during the Jamaican's Berlin 100m world record sprint nine years ago.