Substitute Timo Werner scored one and set up another in the second half to cancel Naldo's equalizer as Leipzig moved a point above Schalke, and 13 behind leader Bayern Munich.
"Keita will play against Schalke this weekend and hopefully he'll play well".
In a bid to replace Philippe Coutinho, who joined Barcelona earlier in the week, Liverpool are understood to want to push forward Keita's arrival on Merseyside.
"Neither the player has told us that he wants to change, nor is there an offer from Liverpool", Rangnick told Sky.
Liverpool reached an agreement with RB Leipzig last summer for the Guinean midfielder to transfer to the English team next summer in exchange for €75 million ($91.5 million). He might have got another for a foul on Max Meyer before Leipzig coach Ralph Hasenhuettl chose to take him off with just over 20 minutes remaining.
Gomez was playing his first competitive game for Stuttgart since rejoining the side in a winter transfer from Wolfsburg.
Recent reports suggested that Liverpool were looking into the prospect of bringing the move forward by five months, though, as they are keen to bolster their midfield ranks for the business end of the current season.
The defeat leaves Mainz 15th in the table, just a point above the bottom three, while Hanover climb to 10th.
Eintracht Frankfurt blew the chance to jump from ninth to third after French striker Sebastien Haller gave them a lead at home to Freiburg, who equalised through a header by defender Robin Koch in the second half in a 1-1 draw.
Augsburg defeated Hamburger SV 1-0 to leave the visitor stuck in the relegation zone.