By Karolos Grohmann
REUTERS - RB Leipzig's title credentials will come renewed attack on Saturday as the Bundesliga's surprise leaders host Schalke 04, who have shaken off a dreadful start to go 12 games unbeaten in all competitions.
Leipzig's rise to the summit has shaken up the division with the unbeaten East German club having won their last seven league matches to top the table, three points ahead of champions Bayern Munich.
Leipzig coach Ralph Hasenhuettl will have his top scorers Timo Werner and Emil Forsberg fit again after minor muscle injuries forced them to train alone earlier this week.
Defender Marvin Compper, however, is still doubtful after he suffered an ankle injury two weeks ago.
"It is difficult to say given he (Compper) can't do anything at the moment," Hasenhuettl said. "It will be tight for him for Saturday.
"We know Schalke want to take something away from the game against us and we are ready and looking forward to it."
Schalke are also in devilish form, having won five of their seven most recent Bundesliga matches, stretching their unbeaten run to 12 games in all competitions after they opened the campaign with five straight league defeats.
Apart from Leipzig, they are the league's most successful team in the last seven matches and have since jumped from last place to eighth in the Bundesliga, with club bosses having kept faith with new coach Markus Weinzierl despite their bad start.
"The team remained calm. The coach and management always found the right words and kept believing in us," said Schalke captain Benedikt Hoewedes.
Hoewedes will come up against his former coach Ralf Rangnick, Leipzig's sporting director, who made the defender captain at Schalke back in 2011.
"I know how Ralf Rangnick thinks. Leipzig are a dominant team and you can see how much work has been put into it," said Hoewedes. "You have to respect that and we have now been warned.
"But with 17 points from seven unbeaten matches in the league it is clear we want points in Leipzig as well."
Bayern can reclaim top spot -- at least for a day -- when they travel to Mainz 05 on Friday, with the Bavarians on 27 points in second place.
Borussia Dortmund, in seventh on 21, will look to rebound from last week's defeat to Eintracht Frankfurt with a win over Borussia Moenchengladbach.
Third-placed Hertha Berlin, on 24, travel to VfL Wolfsburg, struggling in 14th place, two points above the relegation playoff place.
(Reporting by Karolos Grohmann; Editing by Toby Davis)