PHOENIX (AP) – Arizona Diamondbacks manager Bob Melvin has been fired.

A person was familiar with the decision confirmed Melvin’s dismissal. The person told The Associated Press of the decision on condition of anonymity because it had yet to be announced.

Melvin’s firing comes after a disappointing start by the Diamondbacks, who entered Thursday 8 games behind the Los Angeles Dodgers in the NL West. He had one year left on his contract.

Arizona lost 4-3 in 10 innings at San Diego on Thursday afternoon. KTAR, the team’s flagship radio station, was the first to report that Melvin would be replaced.

A message left on general manager Josh Byrnes’ cell phone was not immediately returned.

It was not known who would replace Melvin, the winningest manager in the team’s brief history.

The Diamondbacks were expected to return from San Diego on Thursday, and the team opens a six-game homestand against Washington on Friday night.

Speculation about Melvin’s future grew as the Diamondbacks’ attack sputtered this year.

Arizona entered Thursday with a .225 batting average, by far the worst in baseball.

Team president Derrick Hall, speaking on KTAR on Thursday morning, called the team’s play “unacceptable.”

Melvin was criticized as young players such as Justin Upton, Chris Young, Conor Jackson and Mark Reynolds struggled at the plate or in the field.

It didn’t help that the Diamondbacks lost ace Brandon Webb, who went on the disabled list with a shoulder injury shortly after his opening-day start. Webb has yet to return.

The 47-year-old Melvin was hired in 2005 and went 337-340 with Arizona. He was named NL Manager of the Year after leading Arizona to the division title in 2007.

Melvin came to Arizona after a two-year stint in Seattle, where he went 156-168.

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