Barcelona manager Hansi Flick was not overly impressed with Karim Adeyemi on his debut for the club against Birmingham.Adeyemi joined Barca from Borussia Dortmund at the start of July, waiting a month to make his first appearance.Adeyemi made his Barcelona debut in their friendly loss to BirminghamGettyHe started for the Spanish giants against Championship side Birmingham during their match on Friday evening, which saw Barcelona lose on penalties after playing out a 2-2 draw.However, the German winger was substituted at half time, along with three other of his new teammates.During his first 45 minutes as a Barca player, Adeyemi had one shot at goal, which was blocked in the opening stages.He completed 76 per cent of his passes, but failed to complete a dribble and lost possession nine times in total.His manager, Flick, then admitted that he was not very impressed with his compatriot’s performance on his debut.“Karim, some things he did were not that good,” he said post-match.Although Flick did add: “I think he has more potential to show, but he is still in the first week of training, so that’s normal.“I’ve seen a better Karim in training with his speed and finishing, but he has a lot of potential and can give us a lot.” Of course, after just 45 minutes of action, Adeyemi retains the belief of his boss, but it seems he’s getting some tough love.Flick opted not to try and sign Manchester United’s Marcus Rashford on a permanent deal this summer, getting Adeyemi in instead.Adeyemi lost the ball nine times in his 45-minute first appearance for BarcaGettyAdeyemi’s next outingAdeyemi will have another chance to make his mark at Barcelona in their next pre-season friendlies on August 8.Barca take on Nottingham Forest and Udinese on the same day, with both games being played in Italy. He would have had another game in England after taking on Birmingham, but a scheduled match against Preston North End was cancelled on Sunday.Flick’s men are set to travel back to Spain at the start of the week before their next friendlies in Italy.Barcelona’s first LaLiga game of the season is against Elche on August 23, after another pre-season match against Egyptian side Al Ahly.Adeyemi will hope to make a similar impact to Rashford, who provided 14 goals and 14 assists in 49 appearances last season.For Dortmund last term, Adeyemi scored ten goals and provided seven assists across 39 games in all competitions.