The current season has had little joy for Borussia Dortmund, who effectively dropped out of the race to win the Bundesliga in December and were recently eliminated from the Champions League. But Jurgen Klopp's men have pulled themselves together as of late, beating Real Madrid, Bayern Munich and Wolfsburg (twice) in their last four games, claiming victory by an aggregate margin of 9-1. And on Saturday they face their next test, a home game against Mainz.
The most recent victory over Wolfsburg saw BVB book their place in the DFB-Pokal final, where they will face early Bundesliga title winners Bayern on May 17. It is the Ruhr side's last hope of winning silverware this spring, but in the meantime there are four more league fixtures to be played. Second place in the Bundesliga is still on the line and BVB will be keen to be on a good run of form by the time they face Bayern. With that in mind, here is Klopp's most likely starting XI to take on Mainz:
Goalkeeper: Roman Weidenfeller
With just five games left to be played this season, Roman Weidenfeller is unlikely to be given a break. The veteran goalkeeper has nerves of steel and as vice-captain his leadership is critical to BVB's defensive success. Given that he's only been rested for one Bundesliga game this season, he should start ahead of Mitch Langerak.
Right-Back: Lukasz Piszczek
Lukasz Piszczek played against Wolfsburg but should be relatively well-rested, having sat out of two of BVB's last four Bundesliga matches. The 28-year-old could start at right-back, allowing versatile winger Kevin Grosskreutz a well-earned break.
Center-Back: Sokratis Papastathopoulos
Sokratis Papastathopoulos was on the bench for the Bayern and Real matches, but it would be a mistake to assume that the Greek defender had lost his starting role to Manuel Friedrich. The 25-year-old is younger, fitter and more capable of playing regularly than the ex-Leverkusen man, who until November was retired.
Center-Back: Mats Hummels
Mats Hummels has been a constant presence in defense for BVB as they've conceded just once in their last four competitive games. The center-back is a hugely important stabilizing force for Dortmund and is in fine form as he targets a starting role for Germany at the World Cup.
Left-Back: Erik Durm
Marcel Schmelzer is nearing closer to recovery from a muscular injury, but at this point he is still not fit. That means Klopp still has some time before he is forced to make the difficult decision of whether to start the established Germany international or Erik Durm, who has been outstanding as of late and shut out such top-class wingers as Gareth Bale and Arjen Robben.
Defensive Midfielder: Sebastian Kehl
Like Durm, Sebastian Kehl is more or less assured of his starting role for the time being; the captain will play in the absence of injured midfield anchor Sven Bender. The 34-year-old has generally impressed this season and his leadership is key to the team's success.
Defensive Midfielder: Nuri Sahin
Nuri Sahin and Milos Jojic have rotated in recent games, and on Saturday it will be the Turkey international's turn to start. Sahin played very well against Bayern a week ago and despite the emergence of Jojic, should have Klopp's full confidence.
Right-Winger: Jonas Hofmann
Jonas Hofmann was given a rare start last week and scored with an emphatic volley. The 21-year-old is by no means a starter in Dortmund's best team, but his performance ought to have earned him another start. Given that Kevin Grosskreutz has started every game since early February, it would be natural for Klopp to give the versatile wing player a break and allow Hofmann another chance to build on his form.
Left-Winger: Henrikh Mkhitaryan
After a dismal performance against Real Madrid just over a week ago, Henrikh Mkhitaryan has rebounded brilliantly. The Armenia international scored the openers against Bayern and Wolfsburg and, although he no longer is playing in the central position that perhaps suits him best, is truly in outstanding form. He'll start on one wing or the other, depending on whether Hofmann, Grosskreutz or Pierre-Emerick Aubameyang starts on the opposite flank.
Supporting Striker: Marco Reus
Marco Reus was moved from the wing to a central role for the second leg of the Real tie and has since exploded into arguably the best form of his career. He was twice on target against Madrid and has scored seven goals and assisted four more in his last six matches. He'll get the nod in the center of attack just off the main striker.
Striker: Robert Lewandowski
Robert Lewandowski was on target against Wolfsburg and can expect to start against Mainz. The physical nature of Thomas Tuchel's side can be a problem for BVB, who will want the combative Poland international in their first team.