Chelsea were forced to settle for a draw at the Mestalla as Roberto Soldado's late penalty for Valencia cancelled out Frank Lampard's opener.
Lampard latched onto Florent Malouda's pass just before the hour mark to give Chelsea a deserved lead after a period of supreme dominance.
However, Salomon Kalou - a late replacement for Lampard - gave away a needless penalty to ensure the home side salvaged a point with only four minutes remaining.
Chelsea just edged a tight first half, with Fernando Torres seeing claims for penalty rejected and Ramires also being hauled down when through on goal.
Much was made prior to kick off of Andre Villas-Boas' recent treatment of Lampard, but the Portuguese's decision to go with the veteran midfielder from the outset eventually paid dividends.
After Diego Alves had made two remarkable saves to prevent Fernando Torres opening the scoring, Malouda found Lampard with a cut-back from the right and the 33-year-old slotted home from inside the penalty area.
However, as Chelsea appeared to be holding out for a second win of the Champions League group phase, Kalou handled from a Valencia corner to provide Soldado with the chance of levelling up.
The in-form forward made no mistake from the spot - sending Petr Cech the wrong way - while Nicolas Anelka spurned an opportunity in stoppage time; hitting his shot straight at an advancing Alves.