The A's might have thought about bringing Blake Treinen back, but the former All-Star closer will be turning in the green and gold for Dodger blue.

Treinen has agreed to a one-year, $10M contract with the Los Angeles Dodgers, ESPN's Jeff Passan reported Wednesday, citing sources.

Right-hander Blake Treinen is in agreement with the Los Angeles Dodgers on a one-year, $10 million deal, sources tell ESPN. Treinen had multiple offers in that range and chose the Dodgers. — Jeff Passan (@JeffPassan) December 11, 2019

Treinen broke out in 2018 for the A's, collecting 38 saves while putting up a microscopic 0.78 ERA and a 0.83 WHIP. But 2019 was a tough season for the right-hander. Treinen struggled early and lost his closer job to All-Star Liam Hendriks.

The right-hander fought to regain his All-Star form from a season ago, but was unable to recapture the magic, putting up a 6.14 ERA during the second half to the season.

The A's opted to non-tender Treinen last week. General manager David Forst had said the A's remained in contact with Treinen, but it appears the reliever felt a change of scenery was for the best.

In joining the Dodgers, Treinen becomes part of a bullpen that president of baseball operations Andrew Friedman felt needed an upgrade. All-Star closer Kenley Jansen has seen his effectiveness waver over the past two seasons, and last offseason prize Joe Kelly was inconsistent at best in Year 1 in LA.

The Dodgers have one of the more complete rosters in baseball, but adding a reliever who can get big outs late in the game is a must for any World Series contender. Whether or not Treinen can return to his 2018 form remains to be seen.

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As for the A's, they still are trying to decide what MVP finalist Marcus Semien's future in Oakland looks like and will turn their attention to filling out the bullpen in due time.

While there aren't a lot of top-tier relievers on the open market this offseason, the A's should be able to fill Treinen's with a low-cost, high-upside option that Billy Beane has been known to unearth.