Pep Guardiola has called Kyle Walker’s kicking of an RB Leipzig player “stupid” with the defender banned for tonight’s Champions League visit of Sporting. That has left the Manchester City manager with only 14 senior players available. João Cancelo is ill, and Nathan Aké and Rúben Dias are injured, leaving Guardiola without four frontline defenders. Walker will serve the second match of a three-game suspension during the last-16 second leg against the Portuguese champions after lashing out at André Silva in a final group match which had no significance for City, who had already qualified. The club appealed against the punishment, though Guardiola did not agree with this. “He deserved the three-game ban,” the manager said. “When a player does a stupid thing, he deserves [punishment]. I’m not so kind to Kyle in this kind of action. I’m still so angry with him. “Kyle is so important for us – you saw the game he played against Man Utd [on Sunday]. But in Leipzig when we had already qualified, 80 minutes in and he made this kind of action? The club appealed but I did not agree. They have to do it because in other similar cases it was just two games [but] he deserved it. Hopefully he learns for the future. “We have just 14 players available. We have a few problems, the suspension for Kyle, João is sick. We are in a little bit of trouble behind, in the back four. Of course we had an incredible result in the first leg, we start 5-0, but it is not done.” Guardiola could opt to field John Stones at right-back, Aymeric Laporte and Fernandinho in central defence and Oleksandr Zinchenko at left-back. Kevin De Bruyne will miss the team’s next European game if booked. “Maybe he will not start,” Guardiola said. Ederson believes City, who are the Premier League leaders and in the FA Cup quarter-finals, can win these competitions and the Champions League to claim the Treble. “Definitely,” the goalkeeper said. “We’re fully capable of meeting this objective.”