Chelsea took an early lead through Fernando Torres and had chances to extend their advantage but Aurelien Chedjou scored midway through the second half for the hosts to level the tie.
"This is Turkish football, it's very emotional, Galatasaray are a big club with big players and it was not easy," Mourinho said.
"The first half we had chances to kill game, I am not criticising our strikers but they had chances to do the second goal, and that would have changed the game.
"In the second half they put pressure on us, they had attacking full-backs and powerful strikers, and they put pressure on us. Fernando Torres and Andre Schurrle were in trouble in the second half, they were a bit exhausted. But we were comfortable, until we conceded at the corner.
Mourinho said he could not complain after problems with midfielders John Obi Mikel and Oscar and coping with players who were unavailable.
"The performance of the players in a difficult place to play was amazing," he said. "I just ask for 10 per cent of what this stadium gave Galatasaray when we play in three weeks.
"It's better to be 1-1 than 0-0, this result is better than the 0-0 we had in the first minute, it's not a bad result but they are an experienced team with good strikers and we will have work to do."
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