Jim Harbaugh, Niners mutually part

— -- Jim Harbaugh and the 49ers have mutually agreed to part ways, officially ending his star-crossed tenure in San Francisco.

The Niners issued a statement shortly after Sunday's season-ending victory over Arizona, confirming their split with Harbaugh and saying that they already have begun their search for another head coach.

"Jim and I have come to the conclusion that it is in our mutual best interest to move in different directions," Niners CEO Jed York said in the statement. "We thank Jim for bringing a tremendous competitive nature and a great passion for the game to the 49ers. He and his staff restored a winning culture that has been the standard for our franchise throughout its history. Their commitment and hard work resulted in a period of success that should be looked back on proudly by our organization and our fans. We wish Jim and his family all the best."

"For the last four seasons I have had the great privilege to coach one of the storied franchises in the history of football," Harbaugh said in the statement. "We accomplished many great things together as a team during this period, which is a tribute to the incredible efforts of some of the most dedicated players and coaches in the NFL. I will miss competing alongside this group of players and coaches, I have the utmost respect and admiration for their hard work and support. It has been my honor to share the sideline with these mighty men. I will always appreciate and remember fondly, the passion and support of our Faithful fans, and want to express my particular thanks to them."

Despite the 49ers' overall success during his four-year tenure, Harbaugh's frequent clashes with team management -- specifically general manager Trent Baalke -- fueled speculation about his job security. The Niners went 44-19-1 in their four years under Harbaugh.

Harbaugh has been linked to several coaching vacancies and expected openings in recent months, including the job at the University of Michigan, his alma mater.

The Niners missed the playoffs for the first time under Harbaugh by going 8-8 this season en route to a disappointing third-place finish in the NFC West.

Harbaugh's first three seasons in San Francisco were marked by overwhelming success, as the Niners appeared in the NFC Championship Game three straight times and reached Super Bowl XLVII, where they were defeated by John Harbaugh's Baltimore Ravens.

But after getting off to a 7-4 start this season, San Francisco struggled down the stretch, losing four of its final five games.

Harbaugh's fourth season with the Niners was marred by the shortcomings of quarterback Colin Kaepernick, who regressed in his second full year as the starter, the lengthy absence of star pass rusher Aldon Smith, who was suspended nine games for multiple violations of the NFL's personal conduct policy, and the off-field troubles of defensive lineman Ray McDonald, who was released earlier this month following an allegation of sexual assault.