The case has been solved. 

After Pirates bench coach Don Kelly bowed out of the race, the Mets had one more "mystery" candidate to speak with before concluding the first-round of interviews in their managerial search.

And this unknown individual turned out to be a big surprise in Dodgers first base coach Clayton McCullough. The New York Post first reported that McCullough interviewed with the Mets on Thursday.

McCullough, 41, has spent the past seven seasons with the Dodgers. He joined the organization in 2015, serving as their minor league field coordinator until last year when he got promoted to first base coach on the major league staff.

Prior to heading to Los Angeles, McCullough managed in the Toronto Blue Jays' minor league system from 2006-2014. It was there that he complied an impressive record of 629–559 during his time in the organization, managing between rookie and Class-A ball.

McCullough was selected in the 22nd round of the 2002 MLB Draft out of East Carolina University by the Cleveland Indians, who are now known as the Guardians. During his time with the Indians, McCullough played three seasons in the minors from 2002-2005 before pursuing a coaching career.

Mets director of analytics, Ben Zauzmer worked for the Dodgers for six seasons before coming to New York last winter. While their level of familiarity is currently unknown, both Zauzmer and McCullough were with the Dodgers' organization for a number of years together.

McCullough was on the Dodgers' major league coaching staff with bench coach Bob Geren last season, who also interviewed for the Mets' managerial job this week.

The Mets were believed to have wrapped up the first-round of the interview process with McCullough today. Now, the final stage for the candidates who will move on is a face-to-face conversation with team owner Steve Cohen.

These interviews could come as soon as this weekend and will include no more than three candidates, per SNY.

New York spoke with Buck Showalter (the favorite), Joe Espada, Matt Quatraro, Don Kelly (bowed out), Brad Ausmus, Bob Geren and McCullough in the first-round of interviews in their managerial search.

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