A five-match unbeaten run in the Bundesliga has Schalke sitting third, six points clear of Bayer Leverkusen with a game in hand.
Victory at the Weserstadion would almost guarantee Keller's team an automatic UEFA Champions League place.
Keller wants to see their run continue, with his side set to be boosted by the return of Kevin-Prince Boateng from suspension.
"We're on a bit of a run," he was quoted as saying by the Bundesliga website.
"We want to extend that in Bremen, then we can play without any pressure. It's important that we carry on picking up points and if we succeed in that, then we'll qualify for the Champions League again."
The return of Boateng could be an opportunity for Keller to give teenager Max Meyer a rest, with the midfielder having featured in all bar one of Schalke's seven matches in March.
Bremen welcome back Aaron Hunt, who has announced he will be leaving in the off-season, as they look to pull further clear of the relegation zone.
Coach Robin Dutt, whose team are six points ahead of 16th-placed Nuremberg, said the outgoing forward was still performing well.
"We're really going to miss Aaron next year," Dutt said
"But I get the feeling his departure is not affecting him in the slightest. He actually seems to be giving it one last push and I was very happy with the way he played in Hannover."
