Barcelona talisman Lionel Messi finally opened his account against Chelsea with a 75th-minute equaliser to earn his side a 1-1 draw in a fascinating Champions League last 16, first leg duel at Stamford Bridge.
Willian's superb 62nd-minute effort looked like giving Chelsea a precious advantage for the second leg in Spain but they undid all their good work by handing Messi an equaliser.
The Argentine maestro, teed up by Andres Iniesta, struck a low shot past keeper Thibaut Courtois for his first goal in nine attempts against Chelsea.
As expected, Barca dominated possession but Antonio Conte's Chelsea side were unfortunate not to end with a victory after Willian was twice denied by the woodwork before halftime.
The second leg is on March 14 at the Nou Camp.
Meanwhile Bayern Munich, helped by two typical Thomas Mueller goals and two from Robert Lewandowski, romped to a 5-0 win over Besiktas in their tie after the Turkish champions played nearly the whole match with 10 men.
Besiktas defender Domagoj Vida was given a straight red card for tripping Lewandowksi outside the penalty area in the 16th minute, the defining moment in the round of 16, first leg tie.
Mueller, inelegant yet always effective, broke the deadlock with a miskick two minutes before half-time to break Besiktas's resistance.
Kingsley Coman and Mueller added two more before Lewandowski helped himself to a late brace, virtually assuring the Bavarians of a seventh successive quarter- final appearance.