Asmir Begovic endured a difficult debut as Chelsea suffered a 4-2 loss to New York Red Bulls in the International Champions Cup.
Loic Remy opened the scoring with an emphatic strike in the first half and had the chance to double the lead, but failed to divert a cross into an open goal.
The Red Bulls were level shortly after the break when second half substitute Begovic was tackled by Franklin Castellanos, who finished into an empty net after a poor pass from John Terry.
Begovic was beaten again midway through the second half by a header from 16-year-old Tyler Adams, before Sean Davis slotted home from close range.
Eden Hazard pulled a goal back for Chelsea but Davis scored again as a disorganised Chelsea back line fell apart after the interval.
The Red Bulls were impressive from the outset on home soil, with Davis sending an early warning shot at Thibaut Courtois, who scrambled across his line following a miscued effort from long range.
Chelsea's physical presence at set-pieces proved troublesome and Branislav Ivanovic and Kurt Zouma almost combined for the opener approaching the midway point of the first half, but the latter was unable to steer his header inside the post.
However, Chelsea were not to be denied seven minutes later thanks to Remy, who adjusted his body, took an extra touch and fired the ball into the net, having been picked out by Oscar.