With Manchester United set to lose Nemanja Vidic this summer, and Rio Ferdinand's future uncertain, the club's next great central defensive partnership is up for grabs.
Whether it be a player coming into the backline, or any of the trio of Jonny Evans, Phil Jones or Chris Smalling, it's all to play for - and the defenders already at the club in some ways are performing an audition between now and the end of the season.
Current United forward Danny Welbeck believes that it is Chris Smalling who has all the assets to be a great, stating that even accounting for Vidic and Ferdinand, he finds him the most difficult centre-back to face in training.
He told ManUtd.com: "I would have to say Chris Smalling is the most difficult to get past in training. He’s one of our fastest players and can rival most of the forwards for pace.
"He also reads the game really well and is always in the right place at the right time, clearing up any danger.
"I’m just glad that I get to play with him for both United and England. I’d hate to play against him!"
Smalling, 24, has made 22 Premier League appearances this season, with 18 of them starts. Of those however, 13 have been at right-back and 10 at centre-back.
With Rafael da Silva missing training on Monday and unlikely to feature against Bayern, it could be that Smalling's chance to shine against the Germans is most likely to come on the right, if he is preferred to Phil Jones.