Chelsea scored late to rescue a 2-2 draw in their first pre-season friendly under Enzo Maresca.
Wrexham pushed the Blues all the way in Santa Clara on Wednesday night despite deservedly falling behind to a Christopher Nkunku strike in the first half.
Luke Bolton and Jack Marriott took advantage of slack defending to swing the game their way before Lesley Ugochukwu grabbed an equaliser with seven minutes to go.
