Chelsea maintained their perfect start to their Europa Conference League campaign by beating Heidenheim 2-0 on Thursday. 

Two second-half strikes from Christopher Nkunku and Mykhailo Mudryk kept the Blues top of the pile after four games, taking their total to 18 goals in this year's competition.

The visitors thought they had been awarded a penalty when Mudryk was tripped inside the box, and despite being told to go to the monitor to review the decision, referee Serdar Gozubuyuk stuck with his original call. 

However, the Blues found themselves in front six minutes after the break when Jadon Sancho's cross was gathered by Nkunku, who finished with aplomb from inside the area. 

Heidenheim continued to ramp up the pressure late on and thought they had levelled through substitute Maximilian Breunig's diving header, but the offside flag was raised on the far side. 

The victory was sealed in the 86th minute after fine build-up play between Sancho and Kiernan Dewsbury-Hall saw the ball pulled back for Mudryk, who rifled into the top corner.

Cesare Casadei's sending off in second-half stoppage time took the gloss off an otherwise impressive display, with the Blues' focus now turning to Aston Villa this weekend. 

Chelsea lead the league phase of the competition and are on the brink of the last 16. Maresca praised the mentality his side showed to stay perfect in the competition.

"It was a very good challenge for all the aspects, they were high pressing, intense, but no matter what they do, it's important we are ready," he added.

"It's important to continue with that mentality."

Data Debrief: Blues march on

Following Chelsea's 8-0 thrashing of Armenian minnows Noah in their last game, many placed the Blues as favourites to win this year's competition, but they were made to work for their triumph in Germany. 

While the Blues accumulated an expected goals (xG) total of 2.9 to Heidenheim's 1.97, the hosts registered more shots on target (11), but were foiled by the brilliance of Filip Jorgensen, who made 11 saves during the encounter. 

Nkunku also continued his scoring streak in the competition, netting his fifth Europa Conference League goal, while also producing more shots on target (three) than any of his team-mates.