HILDESHEIM, Germany (AP) -- Borussia Dortmund is leading the way in the Bundesliga where defending champion Bayern Munich is keeping pace thanks to its knack of scoring late goals.
Dortmund has made the best ever start any side has made to the Bundesliga after four games, with four victories and a goal difference of plus 12. Thomas Tuchel had steered the side to a club-record start of nine wins from nine competitive games across all competitions before Thursday's Europa League opener against Russian side Krasnodar.
Bayern needed last-minute goals against Augsburg last weekend and Hoffenheim two rounds before to keep pace.
However, Dortmund, which leads on goal difference, faces a tough test against Bayer Leverkusen on Sunday, while Bayern will be expected to prevail at promoted Darmstadt on Saturday.
Here are some things to know about the fifth round of games:
DORTMUND IN DREAMLAND
Dortmund's travails last season seem a long time ago as the side appears reinvigorated under new coach Thomas Tuchel. Henrikh Mkhitaryan looks like a different player, Ilkay Gundogan seems to be back to his best, and Pierre-Emerick Aubameyang has been clinical in front of goal, scoring eight and setting up three more across Dortmund's nine games, with five goals scored alone in the league.
Last season's difficulties prompted Tuchel's predecessor Juergen Klopp to announce his departure after seven seasons in charge. The troubles began after just nine seconds of the league when Karim Bellarabi scored for Leverkusen in their opening game.
Bellarabi and Leverkusen visit again Sunday, when Dortmund will be wary of a repeat.
Promoted Darmstadt has impressed on its return to the Bundesliga with three draws and a win over Leverkusen from its opening games. It is one of just four teams to remain unbeaten, though Bayern is visiting next.
"Bayern sets the benchmark. It's going to be a fantastic atmosphere," Darmstadt forward Marcel Heller said. "We'll give it full gas and then see what's possible. But we mustn't shed any tears if we don't win."
Bayern has lacked urgency in its opening games, failing to turn possession into goals and leaving victories too late for comfort. But Wednesday's 3-0 win at Olympiakos in the Champions League suggests the side is getting back to its best, with Thomas Mueller in particular in fine form.
Mueller scored twice in Piraeus, taking his tally to 11 goals in seven games for Germany and Bayern since the season began.
'GLADBACH'S NIGHTMARE START
Borussia Moenchengladbach has endured a nightmare start to the season, with four defeats in the league and a 3-0 loss at Sevilla in its Champions League opener on Tuesday.
There will be no sympathy from Cologne in the Rhine derby on Saturday. Cologne suffered its biggest defeat under coach Peter Stoeger last weekend, 6-2 at Eintracht Frankfurt, and will be keen to bounce back in front of its own fans.
"Now we've all been given a shake and are at the bottom of things. Perhaps that's not so bad before the derby," Cologne goalkeeper Timo Horn said. "These are games in which you can atone, put things behind you."
'Gladbach coach Lucien Favre, who has had to cope with injuries, player suspensions and injuries, will be thinking the same.
Stuttgart is also looking for its first win after four straight losses but faces another tough challenge as resurgent Schalke visits on Sunday.
Schalke coach Andre Breitenreiter's softly-softly approach appears to be paying dividends for his young team. The former Paderborn coach is trying to buy time and keep expectations down so players can develop away from the pressure-cooker atmosphere that traditionally surrounds the club.
Last Sunday's 2-1 win over Mainz wasn't pretty, but it showed a growing strength of character as Schalke climbed to fifth.
Stuttgart coach Alexander Zorniger has no such luxury after his first games in charge. The 47-year-old desperately needs a win to get his side out of a rut.
Wolfsburg is still trying to adjust following the departure of Kevin de Bruyne, but showed signs there is life after the Belgium midfielder in its Champions League win over CSKA Moscow on Tuesday.
Julian Draxler, who arrived from Schalke thanks to some of the proceeds from De Bruyne's sale, clinched the game's only goal and produced his best performance for some time. Dante, another new arrival, also impressed.
"A bit of time is needed before we reach the level that we had before," said Wolfsburg captain Diego Benaglio, whose side has slipped to two draws in the Bundesliga already.
Wolfsburg hosts Hertha Berlin on Saturday.