Semien burns former team, stuns A's with walk-off homer

Marcus Semien celebrates

Former Athletics shortstop Marcus Semien had dinner with current Oakland players Tony Kemp and Khris Davis on Thursday night in Toronto.

A night later, Semien broke their hearts with a walk-off three-run homer to cap a wild game that saw the Blue Jays rally from two separate multi-run deficits to stun the A's 11-10 on Friday night at Rogers Centre.

Semien's 34th homer of the season was the ultimate revenge against the team he spent the previous six seasons with.

The A's decided not to re-sign the Bay Area native Semien over the winter, and after signing a one-year contract with the Blue Jays, he is having an incredible season in Toronto.

In addition to all the homers, Semien now has 81 RBI this season, setting himself up for a big pay day this offseason.

The A's took an 8-2 lead into the bottom of the eighth inning, but Lou Trivino and Yusmeiro Petit combined to allow six runs, including a game-tying grand slam to Lourdes Gurriel Jr.

Mark Canha gave the A's a 10-8 lead with a two-run homer in the top of the ninth, and manager Bob Melvin turned to Sergio Romo to try to close the game out.

Instead, Romo never recorded an out. He gave up a leadoff single to Breyvic Valera and a double to George Springer, which set the stage for Semien to burn his former team.

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The Cal alum did just that, sending a 370-foot homer into the left field seats.

The homer by Semien left Kemp in utter disbelief.

The A's have suffered some tough losses in recent weeks, but this one will sting even more based on who inflicted the pain.