Sterling, 18, and Allen, 22, had their least ineffective games of the season during Saturday's 3-1 defeat against Aston Villa at Anfield and the Liverpool manager accepted the pair's level of play has started to taper off.
"I think there is an element of (fatigue) but not with (someone like) Luis (Suarez)," said Rodgers. "He's at his best when he is playing regular. He will tell you himself, if he was playing one game a week he would lose his rhythm - he likes to play lots of games.
"But I think there are others we need to give a break. There is no doubt Raheem is one who does need that breather. I've thought about it over the past couple of weeks. In order to do that you need to have that depth to take him out and put somebody else in.
"That's something I'm thinking about - who to put in. He's a naturally very, very fit boy but he needs that mental rest as well. For the kid as well, it's about efficiency as well, tactically he's still very young. That time will come and he will get the breather soon enough.
"There is no doubt after working with Joe (before at Swansea) and seeing him (now), he's another one. If we're honest, there are a few who could do with that breather, especially mentally. It's something for sure I need to have a wee look at.
"This was a game where we had to get an early goal and make Villa come out. We had a wee bit of lethargy. I don't know why because it's one of the first weeks we've had without a midweek game, and we couldn't have had a better week."