A goal from Nigeria striker Victor Boniface with 11 minutes remaining earned Bayer Leverkusen a 1-1 home draw with Borussia Dortmund on Sunday, keeping the league leaders' unbeaten record this season intact.

Dortmund scored just five minutes in through Julian Ryerson and the visitors looked set to be the first side this season to beat Leverkusen in any competition.

With the clock running down, Leverkusen manager Xabi Alonso brought Patrik Schick from the bench and the move paid immediate dividends, with the Czech attacker finding Boniface for the equaliser.

An "unhappy" Leverkusen midfielder Florian Wirtz told DAZN "even if we managed to equalise, when you see the match we would have hoped for better and we should have done better."

Dortmund manager Edin Terzic praised his team's defence in the "fair result", but hit out at VAR, who declined to intervene despite what seemed like a late foul on winger Karim Adeyemi.

"We discuss VAR every week, we discuss clear wrong decisions, about handball and foul play, but that wasn't enough?" Terzic said of the incident.

"That's what really upsets me, because it is not fair."

The draw means Leverkusen end the round three points ahead of Bayern Munich on the ladder, although the Bavarians have a game in hand after Saturday's match with Union Berlin was postponed due to heavy snowfall.

Telling reporters his players "did enough to win", Alonso said his team, who have won 18 and drawn two of their 20 matches this season, needed to "be realistic" about the result.

"We know what we've done until now and we know what we must do. The path is clear and the players are totally convinced of the way forward."

Alonso made eight changes to the XI which won 2-0 at Swedish side Hacken on Thursday, which secured them top spot in their Europa League group.

Coming into the match 10 points behind Leverkusen after just 12 matches, Dortmund were hit with a pre-match wave of the flu, ruling out several first teamers including Donyell Malen, Niklas Suele and Ramy Bensebaini.

Fresh from Tuesday's 3-1 win at AC Milan which secured progress to the Champions League knockouts, Dortmund burst out of the blocks, taking the lead after just five minutes through Ryerson.

With his back to goal, Niclas Fuellkrug held the ball up perfectly before back-heeling to Ryerson, who threaded the ball into the goal.

Leverkusen turned up the heat for the remainder of the opening half but could not find an equaliser, Wirtz's 45th-minute stunner being ruled out by VAR for a narrow offside.

Dortmund held firm amid relentless Leverkusen pressure in the second-half, before Alonso sent on Schick, who had only played one minute in the league this season.

The Czech striker helped Leverkusen equalise less than a minute later, sliding a ball through the Dortmund defence to Boniface, who tapped home from close range.