Chelsea beat Leicester City 1-0 at the King Power stadium on Sunday in an FA Cup game as the Blues are through to the Semi finals.
Barkley was one of the three players Chelsea boss Frank Lampard introduced after the break.
According to Barkley, Lampard told the players at halftime that their performance in the first half wasn’t good enough.
“I thought we weren’t at our best. There were a lot of things we could have done better,” Barkley told BT Sport.
“When you get in the box the chances are there. Getting in the box we’re always going to get goals. We won the game, it’s the most important thing.
“At half-time, the gaffer said it’s not good enough and to be vocal on the pitch, and we improved.”