After a week of rumblings, Chris Mullin has officially stepped down as the men's basketball head coach at St. John's, it was announced Tuesday.

"This has been an extremely emotional decision, but after a recent personal loss, I took time to reflect upon my true values and believe this is the right time to make a change," Mullin said in a statement issued by the school. "I am extremely grateful to the administration, which has supported me and our basketball program on every level.

"I've been amazed by our coaches, trainers, managers and staff who work relentless hours, which enables this team to grow and thrive. I've been honored to coach the young men who are the heart and soul of this program. It's a job I will always cherish."

Mullin, the greatest player in St. John's basketball history, took over as head coach in 2015, replacing Steve Lavin. Mullin struggled in his first three years at the helm, going a combined 38-60 and failing to finish above .500 in any of his first three seasons.

This season, St. John's had one of the most talented rosters in the Big East and made the NCAA tournament, but it stumbled down the stretch, losing five of its final six games. The Red Storm lost to Arizona State in the First Four, finishing their season 21-13.

Speculation surfaced this week amid reports of contentious meetings between Mullin and athletic director Mike Cragg, who issued a statement of support on Saturday.

The past four years at St. John's University have been one of the most thrilling and challenging points of my career," Mullin said in the statement. "... I am proud of our accomplishments. NCAA Tournament Selection Sunday will be a lifetime memory. I am forever grateful to St. John's for giving me the opportunity to hear Carnesecca Arena and Madison Square Garden roar again for college basketball and especially for our players."

Mullin, a member of the Naismith Memorial Basketball Hall of Fame, had no coaching experience before he took the job. He worked in the Golden State Warriors' front office for five years as the executive vice president of basketball operations. He also spent time working as an adviser in the Sacramento Kings organization.

The top target for St. John's is expected to be Arizona State coach Bobby Hurley, sources told ESPN on Monday. Hurley played at Duke, where Cragg spent 31 years before being hired at St. John's in September.

Another name expected to be considered is Iona coach Tim Cluess, who played at St. John's for two seasons and has coached in the New York area his entire career.

Whomever replaces Mullin will have a roster in flux. Leading scorer Shamorie Ponds turned pro after the season ended, while Marvin Clark was a senior. The Red Storm's top recruit, highly-touted junior college point guard Cam Mack, recently requested his release from the school, and four-star junior Nate Tabor decommitted Monday night. There are zero 2019 or 2020 prospects currently committed to St. John's.

There is a solid core on the roster, though. Mustapha Heron (14.6 PPG), LJ Figueroa (14.4 PPG) and Justin Simon (10.4 PPG) all have eligibility left, while transfers Eli Wright (Mississippi State), David Caraher (Houston Baptist) and Ian Steere (NC State) sat out this past season.

ESPN's Jeff Borzello contributed to this report.