City were stunned 2-1, with the XI hit hard by injury.
But Walker said in the aftermath: “I don’t think we’re using that as an excuse. We’ve got players on the bench and players that started today that felt there were fit to start.
“We don’t use that as an excuse. We have to give full credit to Bournemouth and move on, move onto the next one.
“To come here and not get the win is always disappointing.
“Sometimes you have to play the game with emotion.
“Sometimes, when we’ve got the injuries we’ve got, and the lads are tired, and they (Bournemouth) have had six days to prepare for this game and everything like that, sometimes you need to play with your heart.
“I felt in the last ten minutes, we came back into it, but to go 2-0 down, it’s always going to be an uphill battle.”