Former Los Angeles Mayor Richard Riordan has joined Greuel's mayoral campaign. He'll serve as a top adviser on economic issues.
"Mayor Riordan is one of those individuals who brought our city back to life," said Greuel.
Riordan backed fellow Republican Kevin James during the campaign leading up to the primary earlier this month. Greuel has strong support from labor and union groups. It's not clear how they'll react to Riordan's role in the campaign.
Last year, he fought unsuccessfully for a ballot measure that would have changed the pension system for city employees. Unions opposed the measure.
"We both have to keep an open mind, because if we go bankrupt, it's going to hurt the members of the union more than anybody else and we are in big trouble in the city now," said Riordan.
Greuel said she's happy to have both business and labor support.
"I'm pleased to have someone like Mayor Riordan who understands we have to sit at the table, roll up our sleeves and talk about the fiscal crisis," said Greuel.
Eyewitness News reached out to SEIU 721, one of the larger unions supporting Greuel, but it had no comment on Riordan's endorsement.
Meantime, Garcetti picked up an endorsement from fellow Councilman Paul Krekorian this week.
A spokesperson for Garcetti's campaign reacted to Riordan's support of Greuel, saying in a statement, "Maybe Riordan can help Greuel decide if she supports pension reform because she has changed her position every day this week."