Crouch told liverpoolfc.tv: "We've got a lot of quality in the squad and I thought all the boys did well, but Fernando when he came on offered us something different. Credit to him, he got the goal and it all opened up.
The England international was instrumental in Liverpool's second on 85 minutes when he was tripped by Carlos Bocanegra. Referee Stephen Tanner pointed to the spot, though replays were not conclusive on whether the foul was inside the box.
Crouch joked that he would have scored anyway.
"I don't know if it was in or outside the box - it was borderline but I was ready to take a shot and no doubt that would have flown in.
"It was definitely a foul. Sometimes you get them and sometimes you don't, and thankfully Stevie tucked it away really well."