SANTA CLARA, Calif. -- The San Francisco 49ers released former Super Bowl MVP linebacker Malcolm Smith on Tuesday after two disappointing and injury-plagued seasons with the team.

With injuries to receivers Jalen Hurd (back), Dante Pettis (groin) and Trent Taylor (foot), the Niners needed to add some receiver depth for Thursday's preseason finale against the Los Angeles Chargers. They signed veteran wideout Nick Williams, who has bounced around the league since arriving in 2013, to take Smith's spot on the roster.

Smith signed a five-year, $26.5 million contract with the 49ers on March 9, 2017, as one of the first free-agent signings of coach Kyle Shanahan and general manager John Lynch's regime. Expected to provide a steady veteran presence and in-depth knowledge of coordinator Robert Saleh's defense, Smith was never able to stay on the field long enough to do either.

"We brought him in to be our 'backer and he was," Shanahan said. "Malcolm has handled himself with class the whole time, but I know it didn't go the way he wanted it to nor how we expected it. But he was always the player we thought he was and the person. He's a guy I will always have a ton of respect for."

In his two seasons with the team, Smith appeared in just 12 games as injuries prevented him from fulfilling the role that was envisioned when he signed. He suffered a torn pectoral early in his first training camp with the team, an ailment that cost him the entire 2017 season.

Smith was able to make it through the 2018 season but was hampered by Achilles tendinitis and hamstring issues for much of the year. He finished with 35 tackles and a pass breakup while starting five games as the SAM linebacker.

Thought to be a candidate to be released before free agency, Smith and the Niners reworked his contract in the offseason.

While the reconfigured deal kept Smith with the team all the way to Tuesday, the writing was on the wall that his time in San Francisco might be growing short when the Niners signed linebacker Kwon Alexander to a four-year, $54 million deal in the opening days of free agency and selected linebacker Dre Greenlaw in the fifth round of this year's NFL draft.

Greenlaw has had a strong preseason and positioned himself as the team's third linebacker alongside Alexander and Fred Warner. Upon his release, Smith will count for $4.2 million in dead money against this year's cap.

"It definitely shows that we have confidence in the other guys," Shanahan said. "I think (Smith) had an unfortunate time here, especially the first year."

The Most Valuable Player of Super Bowl XLVIII, Smith was a top contributor for the Seattle Seahawks for four seasons after they drafted him in the seventh round in 2011. He spent two seasons with the Oakland Raiders before signing with San Francisco.