Jack Colback admitted Sunderland were always up against it after conceding an early goal at Manchester City last weekend.
The Black Cats went down 3-0 at the hands of the reigning Barclays Premier League champions at the Etihad Stadium.
Aleksandar Kolarov netted a free-kick five minutes in, with Sergio Aguero and James Milner adding further goals.
The defeat was Sunderland's first league loss of the season and Colback conceded that City's breadth of talent showed on the day.
"It's a difficult place to come and we set out not to concede early, but that's what happened," he said.
"We came into the game believing we could get something given the performances last season, but unfortunately it wasn't to be.
"City have got a lot of world-class players and that showed in the end. We had one or two moments where we might have got a goal and changed the game, but their class showed."
Colback pointed to the introduction of Aguero as proof of the depth of City's squad.
The Argentine, who cost City a reported £38m, came off the bench just before the hour and scored within four minutes of his introduction to establish a 2-0 lead.
"They have players who can come off the bench who are world class," Colback explained.
"That makes a difference, especially when they are coming on fresh and that bit sharper.
"Aguero came on, got his goal and that killed the game, really.
"We'll analyse the game, see where we went wrong and move on."