Ashbee has been playing games despite a knee injury, and will have the problem examined after the Bank Holiday fixtures next week. He may be rested when City play Blackpool in the Carling Cup tomorrow.
Andrews missed Saturday's game after going off with an ankle injury suffered while playing against Wolves 10 days ago.
Taylor explained: "Keith will have a scan and until we get the results, we don't know the extent of the injury. It might be three weeks, it might be three months."
That leaves the City manager with Stuart Green, Curtis Woodhouse and Russell Fry competing for midfield positions, but none of them are considered capable of filling Ashbee's holding midfield role, so he has moved for the 21-year-old Liverpool player.
The 5'7" product of the Reds' youth team had made 3 appearances for the first team before Rafa Benitez took over last year, and that's when he really made his breakthrough. As well as being captain of their reserve side, he made four cup appearances, and three Premiership appearances toward the end of the season. He was rewarded with a new contract keeping him at Anfield until 2007.
He's also a part of Peter Taylor's England Under-21 squad, with four caps and one goal to his name so far.