Leverkusen have four wins and as many draws in their last eight league matches, a run that has enabled them to quietly climb the table up into sixth place on 20 points, one behind a free-falling Dortmund.
The team, coached by former Dortmund stalwart Heiko Herrlich, have gradually grown in confidence after a slow start to the campaign, with striker Kevin Volland netting in all three matches in November to take his league tally to eight.
Germany international Volland, who scored just six league goals last season, does not need any extra motivation to perform as he battles to earn a place in the squad for next year's World Cup in Russia.
"We have shown this season that if we stay focused over 90 minutes and keep stepping on the gas then we can beat any opponent," Volland said. "But we need to keep working on our consistency."
Herrlich must be relishing the timing of their clash against his former team, with the Ruhr valley club in complete disarray and their last league win coming back in September.
"We have only few injuries. We have been training well and we are in good form at the moment," Herrlich said. "We want to continue that on the weekend, carry that momentum into the game.
"We play against someone who had a great run at the start of the season and managed to score four goals in 25 minutes against Schalke."
Dortmund's troubles appeared well and truly behind them when they raced to a 4-0 lead against their bitter rivals last week but a spectacular second half collapse saw them concede four times without reply in a draw that felt more like a home defeat.
Dortmund have now lost four of their last six league games, with the team sliding down the table after winning six of their opening seven matches under the Dutchman.
Bosz is acutely aware that the Leverkusen clash is most likely his last shot at redemption or he will certainly be sacked.
Bundesliga leaders Bayern Munich, three points clear at the top, host Hanover 96 and will look to bounce back from last week's surprise loss at Borussia Moenchengladbach. RB Leipzig, second on 26, travel to Hoffenheim.
(Reporting by Karolos Grohmann; Editing by John O'Brien)
