The on-loan Arsenal teenager came off the bench after 61 minutes of the 1-0 defeat at Leicester for his first taste of competitive football since suffering a broken leg at Stoke in February.
Davies was impressed with the impact the Wales international made during his short cameo. But he also warned Ramsey may still be short of the fitness required to start, ahead of the visit of Bristol City this weekend.
"We needed to show a variety of passing in possession, but we did not do enough to cause problems," said Davies. "But you could see the difference when Ramsey comes on, then we started to play a little bit better.
"Once he came on, he gave us the quality that we needed. He has outstanding quality, there is no doubt about that.
"Even in a half-fit Ramsey, it is easy to see the quality he has got. We will keep working with him but he is still short of fitness."