It was a rough weekend for San Francisco 49ers running back Marcus Lattimore, a former 2010 NCAA freshman of the year with the South Carolina Gamecocks.

According to NFL Insider Adam Caplan, the second-year ballcarrier will retire from the NFL and is expected to meet with the team Monday.

#49ers RB Marcus Lattimore is expected to retire due to knee issues, a league source confirmed. — Adam Caplan (@caplannfl) November 3, 2014

Expected to be with the team for Sunday’s game against the St. Louis Rams, coach Jim Harbaugh confirmed that Lattimore was not on the sideline and was contemplating his future in the NFL according to CSNBayArea.com.

“Did not see Marcus,” Harbaugh said. “I’m sure we’ll have an announcement about that.”

Sources told CSNBayArea.com that Lattimore, two years removed from a second devastating knee injury that prematurely ended his collegiate career, began experiencing soreness in surgically repaired right knee after two days of practices.

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He did not practice Friday.

A fourth-round pick in 2012, Lattimore was set to return this season after strenuous offseason work to get back into playing shape with a stable knee.

Lattimore rushed for 1,197 yards and 17 touchdowns as a freshman in 2010, leading the Gamecocks to their only SEC Eastern Division title in program history. Here are some video highlights from his excellent South Carolina career: