Christian McCaffrey’s backup lands on IR as 49ers lose 2 running backs in roller-coaster season

Just as the San Francisco 49ers confirmed Christian McCaffrey suffered a season-ending PCL injury in the loss to the Buffalo Bills on Sunday night, his backup is also heading to injured reserve. 

Jordan Mason, who filled in admirably for McCaffrey as he dealt with Achilles tendinitis in both his ankles at the start of the season, will miss at least the next four games due to a high-ankle sprain also suffered in the blowout loss to the Bills. 

The 49ers have no choice but to turn to rookie Isaac Guerendo to be their lead running back for what could possibly be the rest of the season with just five games remaining.

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For McCaffrey, 49ers head coach Kyle Shanahan noted that his star could "potentially" be out for the remainder of the season. 

"I think PCL is usually a couple weeks, but I’m not exactly sure yet," Shanahan said prior to learning that it’s six weeks for him to heal with not that many games remaining on the schedule. 

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At 5-7 after losing three straight, the 49ers are grasping at straws hoping they can go on a run to end the year and get back into the playoffs.

But they currently sit in last place in the NFC West, though the division-leading Seattle Seahawks are only 7-5.

Considering that a running game is crucial for Shanahan’s offense to work, he will be asking a lot of his rookie running back to carry a workload that San Fran was hoping McCaffrey could do after healing his Achilles injuries. 

McCaffrey had 53 rushing yards on seven attempts and two catches for 14 yards before leaving the game on his own power. During one of those runs, he slid after feeling something wasn’t right. 

McCaffrey has played in just four games this season, rushing for 202 yards with no touchdowns on the ground nor through the air. 

As for Mason, he broke out earlier this season, rushing for more than 100 yards in three of his first four games as the lead back with McCaffrey hurt. He slowed down a bit but has still smashed his career highs with 789 yards and three touchdowns.

Guerendo, a fourth-round pick out of Louisville, has tallied 246 yards and two touchdowns on 42 rush attempts over 12 games thus far. 

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