Manchester City boss Manuel Pellegrini says it was vital for his team to take all three points from yesterday's game against Southampton.
The Citizens were coming from back-to-back defeats against Liverpool in the Premier League and Juventus in the Champions League.
But they bounced back in style as they got their title challenge back on track with a convincing win against the Saints.
"It was not an easy week - we've won just one point of our last six so it was important to beat a difficult team who were unbeaten away," Pellegrini told reporters.
"Kun came off as a precaution. I spoke with him before the game and we said he would play 65 minutes. He has a kick in his heel, but nothing important.
"He has played three games in a row and that's why he came off – it's important to see with the medical staff how he recovers from this game.
"I was very pleased with the team's reaction. We were a little nervous until the third goal, but I'm happy with the performance and the result.
"We must try to recover the players for Tuesday. It's important for us to reach the semi-final of the League Cup.
"If you want to be involved in the title race you cannot drop more points at home.
"We've lost already six points against Liverpool and West Ham. It's not easy playing so many games with the same players but I think the start was really important.
"We played on Wednesday a very difficult game and we didn't have 72 hours to recover from that game – Southampton had the whole week.
"The third goal of Alex fortunately killed the game for us - maybe we didn't have a good week but we continue in the Champions League, the Capital One Cup and the Premier League.
"It's not a crisis – it's a very good season."