The Toronto Blue Jays are now entering a potentially franchise-altering offseason.

General manager Alex Anthopoulos is leaving the team after rejecting a contract extension to stay in Toronto, according to multiple reports. The news was first reported by Sportsnet.

The move is a pretty big surprise, at least given the success Anthopoulos and the Blue Jays had in 2015. The Jays won the American League East and reached the American League Championship Series before being eliminated by the Kansas City Royals in six games. However, there have been other recent changes within the organization. The club hired former Cleveland Indians general manager Mark Shapiro as president and CEO in August. It’s unclear what impact that might have had on Anthopoulos’ decision, but reports indicate his decision wasn’t about money or term on the contract.

Anthopoulos was named the Blue Jays’ general manager following the 2009 season. He was one of baseball’s more active GMs during his tenure, with a handful of blockbuster trades marking his time in Toronto.

Some of his best work was his most recent, though. Anthopoulos was able to add marquee players like David Price and Troy Tulowitzki at the trade deadline without adding too much extra payroll. The Blue Jays went 40-18 after the All-Star break, catapulting themselves by the New York Yankees to win the AL East crown.

Thumbnail photo via Nick Turchiaro/USA TODAY Sports Images