Academy starlet Mason Burstow made sure that Chelsea ended their pre-season tour unbeaten with his first senior goal against Borussia Dortmund.

Chelsea had been on top for much of the tie at Soldier Field in Chicago, but it was the Bundesliga side who went ahead with 10 minutes to go, courtesy of a courageously-struck volley from substitute Marius Wolf.

Instead of bowing out, the new-look Blues pushed forward before winning a freekick which Mykhailo Mudryk sent flying into the box, for Burstow to eventually nudge home with cool head.

But a dark cloud sits atop Chelsea’s pre-season silver lining, in the form of the early exit of summer signing Christopher Nkunku, forced off clutching his left knee.

Neither team was able to get off the mark in the first-half, which was marked by scrappy displays from both sides as the two teams looked to get a foothold in the game.

The Blues were brighter in the opening moments, quickly gaining the upper hand and dominance in possession, and they reaped the early rewards with good chances from Levi Colwill and Nicholas Jackson.

Nkunku’s exit in the 22nd minute disrupted Chelsea’s flow, and Terzic’s side attempted to punish their profligacy.

But the Bundesliga side were unable to thoroughly test the Blues, new recruit Marcel Sabitzer coming closest with a missile-like long-range shot that was efficiently blocked.

The second-half saw Edin Terzic’s side look to get off the mark quickly, but the Blues’ centre-back partnership of Colwill and Thiago Silva kept the budding threat at bay.

Before Wolf struck, Jackson looked to fire in the likely winner, with two more good chances, including a break-neck counter-attacking run from inside Chelsea’s half.

But it would be his replacement, the 19-year-old under-21 player Burstow, who ensured that Chelsea return to London without loss with just 11 days before the start of the season.

Chelsea: Arrizabalaga, James (Gusto 73′), Silva (Humphreys 73′), Colwill, Chilwell (Cucurella 73′), Enzo, Gallagher, Sterling (Hall 81′), Chukwuemeka (Maatsen 73′), Nkunku (Mudryk 22′), Jackson (Burstow 81′)

Goals: Burstow (89′)

Booked: James

Manager: Mauricio Pochettino

Borussia Dortmund: Meyer, Bensebaini (Bueno 73′), Ozcan (Nmecha 73′), Reus (Can 73′), Hummels (Blank 73′), Moukoko (Haller 60′), Sabitzer (Brandt 46′), Malen (Bamba 46′), Sule (Papadopolous 60′), Ryerson (Wolf 60′), Adeyemi (Hazard 46′)

Goals: Wolf (80′)

Booked: Ozcan

Manager: Edin Terzic

Tags: Borussia Dortmund, Chelsea, Mason Burstow