The Devon outfit were comprehensively beaten 30-8 by Leicester Tigers, the team that lost to Quins in last year's Premiership final at Twickenham, at the weekend.
Chiefs host Quins on Saturday, and Baxter knows that his side need to up their game against the champions.
"If they look at our performance at Leicester, they will probably fancy coming down to Sandy Park and playing a bit and seeing what happens," said Baxter.
"We have got to be better, of course we have. A lot was made on Saturday about Tigers' injury issues, but we have got a few ourselves as well. I am not a big one to talk about it because I like to back the players who get on the pitch.
"Last Saturday, we had some really good performances in the team, and there will be a handful of guys who will look at their game and be really pleased with what they achieved. I don't think we had enough people doing their jobs flat out on Saturday for us. We didn't play to our potential, we were well beaten and we have just got to move on and get on with it."
Chiefs currently sit seventh in the Aviva Premiership table, whereas Harlequins are second.