Jurgen Klopp's side have climbed from the foot of the table to 10th in recent weeks following four straight league wins.
Italian striker Immobile has continued to draw criticism, but scored both goals in Tuesday's 2-0 DFB-Pokal win against third-tier Dynamo Dresden.
It marked the first time that Immobile has found the net in 2015, taking his season tally to 10 in all competitions and his team-mates recognised the significance.
"I'm delighted to have been able to help the team. After I scored the second goal Mats Hummels came over to me and said I'm really happy for you. Those words did me a lot of good," he told the club's official website.
Marco Reus also picked up what Klopp feared was a serious injury in that match before it was diagnosed as a dead leg, and he could yet be available for Saturday.
Bayer Leverkusen also advanced to the DFB-Pokal last eight on Tuesday, but needed extra time to get past Kaiserslautern and will therefore be grateful that their match against Paderborn is not until Sunday.
Hoffenheim and Freiburg joined Leverkusen in the quarter-finals after preparing for weekend clashes with Schalke and Werder Bremen, respectively, with cup success.
Bremen, however, will be desperate to atone for their midweek Pokal capitulation to third-tier Bielefeld.
Bayern Munich continue their charge towards the title with a trip to Hannover on Saturday, a team Pep Guardiola's men dismantled 4-0 in the reverse fixture in October.
The champions' nearest challengers, Wolfsburg, sit eight points adrift, but can stretch their winning run to five league matches with a victory at faltering Augsburg.
Strugglers Hertha Berlin and Stuttgart meet in the Friday night match before Mainz host Borussia Monchengladbach on Saturday and Eintracht Frankfurt travel to Cologne on Sunday.
