Chelsea manager Jose Mourinho praised Michael Ballack for his contribution to the team's progress to the UEFA Champions League quarterfinals on Tuesday. The under-fire German International scored a late goal for Blues to help them come from behind and earn a 2-1 home victory over Portuguese giants Porto. Mourinho has shown faith in Ballack's abilities and the former Bayern Munich ace repaid his manager and answered critics with the vital goal. "I keep saying that criticism doesn't make me decide to play him," Mourinho was quoted as saying by Sky Sports. "I decide in my mind and from the way I analyze the game. I accept, sometimes, opinions from my assistants - nothing else. "It is one of those goals that is like a stamp. He put in a great effort to play a good game. He was exactly like the team - didn't play well in the first half, but played very well in the second half." Ballack has been heavily criticized for his below-par performances since completing a switch to Stamford Bridge last summer.