The Galaxy had to come from behind twice to draw 2-2 in the California Clasico on Friday against the visiting San Jose Earthquakes.
San Jose led twice in the first half at the StubHub Center thanks to brilliant counter-attacking, with Gyasi Zardes levelling for the hosts at 1-1 just before the half-hour mark, while Omar Gonzalez scored the definitive equaliser three minutes after half-time with a header.
Donovan announced the 2014 MLS season would be his last on Thursday, ending his 14-year career in the United States' first tier of football.
But the Galaxy were unable to ride the momentum of Donovan's revelation to victory against the 32-year-old's former club San Jose.
LA entered the match with four wins in five games and dominated the opening exchanges only for Chris Wondolowski to score against the run of play after 17 minutes.
The Earthquakes stormed forward on the counter-attack and Shea Salinas picked out Wondolowski's diagonal run, before the 31-year-old striker ducked back onto his right foot to finish from a tight angle.
Donovan and Robbie Keane set up the Galaxy's equaliser in the 29th minute with the Irishman's shot deflecting to Zardes, who tucked his effort past Jon Busch.
But San Jose hit the front again just two minutes later with Argentine debutant Matias Perez Garcia thrashing the ball into the net from outside the box, after a fine back-heel set-up from Wondolowski.
The Galaxy dominated the game - they would end the contest with 24 shots to three - but bad luck and poor finishing denied them victory.
Zardes had a goal correctly ruled out for offside late in the first half but Gonzalez dragged the hosts back to 2-2 just after half-time when he stooped to head Stefan Ishizaki's corner into the net.
LA had claims for a penalty turned down in the 64th minute and Keane hit the back of the net in second-half stoppage time only for the goal to be ruled out for a foul, but Bruce Arena's men were unable to find a winner as San Jose held on for a draw.
