Pep Guardiola has told Kyle Walker he is still angry with him for his December dismissal against RB Leipzig which leaves Manchester City without a specialist right back and short of defenders for Wednesday's Champions League last-16 second leg against Sporting Lisbon. With Joao Cancelo ill and both Nathan Ake and Ruben Dias injured, City only have three defenders and just 14 senior players available, leaving Guardiola with a decision over whether to put the veteran midfielder Fernandinho into the back four or to parachute in a youngster from the academy. Walker is suspended after kicking out at Leipzig’s Andre Silva in a dead rubber for City, who had already qualified from the group, and Guardiola revealed he disagreed with the club’s decision to appeal against his three-match ban, in a failed attempt to reduce it to two. The right-back will also miss the first leg of the quarter-finals, which City, <a href="https://www.thenationalnews.com/sport/football/2022/02/15/five-star-manchester-city-thrash-sporting-lisbon-in-champions-league/" target="_blank">boasting a 5-0 lead after their first leg in Portugal</a>, seem very likely to reach. Guardiola is likely to omit Kevin de Bruyne, who is a booking away from a ban, to ensure the midfielder can feature in the last eight, but he remains annoyed with Walker for his needless red card. Guardiola said: “He deserved the three-game ban. When a player does a stupid thing, he deserves to be banned for three games. I'm not so kind to Kyle in this kind of action. I'm still so angry with him. “It's not necessary to discuss with him, he knows it. Kyle is so important for us, you saw the game he played against [Manchester] United? But in Leipzig, when we had already qualified, 80 minutes in and he made this kind of action? He deserves the three games. The club appealed but I did not agree. Hopefully he learns for the future.” The 18-year-old Luke Mbete, who has only made two senior appearances, is a defender who could get an opportunity but Guardiola admitted he does not yet know who his right-back will be. John Stones, who can play there, is needed in the middle of defence without Dias and Ake. “Fernandinho maybe, we’ll speak with some players, we are going to speak about the academy,” Guardiola said. “We are in a little trouble in the back four.” Oleksandr Zinchenko is set to play, despite the trauma caused by Russia’s military operation in his native Ukraine. Ake is expected to be fit soon, but Guardiola said he cannot afford to gamble by rushing the Dutchman back. “It is too risky and with Ruben out for a long time we cannot lose another central defender,” he explained. Fernandinho turns 37 in May and is out of contract in the summer but Guardiola hopes City sign the Brazilian up for a ninth campaign. “I would love it,” he said. “I am so glad to have him. He is an incredible captain. At the end of the season, Txiki [Begiristain, the director of football] and the club have to decide.” Fernandinho already exerts a huge influence off the field and Guardiola argued the midfielder has the potential to become a fine manager as he identified similarities with his former assistant Mikel Arteta, now in charge of Arsenal. “In terms of how the people respect them, definitely,” he added. “After knowledge and passion [comes the] licence to be manager, I’m pretty sure when a holding midfielder is thinking about the team, he has everything to become a manager.” Guardiola guarded against complacency, saying: “We start the game 5-0, but it is not done. Football is unpredictable in many cases. Red cards can be a distraction.” As Walker proved.