SANTA CLARA -- Offensive lineman Colton McKivitz experienced a career's worth of ups and downs last season with the 49ers.
And the way the season began on a down note served as an all-too-real example of just how quickly an NFL career can come to an end.
McKivitz used the lessons learned a year ago and came back this season as a much-improved player.
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Now, he figures to play a key role during a crucial stretch of the 49ers' season with All-Pro Trent Williams expected to miss four to six games with a high-ankle sprain.
McKivitz will be in the starting lineup Monday night, protecting the blind side of quarterback Jimmy Garoppolo, against the Los Angeles Rams at Levi’s Stadium.
“No one’s going to be Trent Williams,” McKivitz said. “He’s probably the best tackle who’s ever played the game, so I’m not going to try to do anything he does or go outside my game.
“At the end of the day, it’s just football, and the results are to get a win. And that’s my biggest thing, to do whatever I can to help us get to that point.”
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McKivitz sustained an injury a week ago when he stepped in a hole on the practice field and rolled his ankle, he said.
So when Williams sustained his injury against the Denver Broncos, the 49ers initially went with Jaylon Moore. When Moore struggled in his first seven snaps, McKivitz got the call.
It is quite a turnaround for McKivitz, who has experienced a little of everything since the 49ers selected him in the fifth round of the 2020 NFL Draft from West Virginia.
Coming off a rookie season in which he appeared in 14 games with three starts, McKivitz had reason to believe he was destined for a long career.
Then, he found himself receiving some unexpected news on the day NFL teams were required to trim their rosters to the regular-season limit of 53 players.
The 49ers cut McKivitz, and no other team came calling. He wound up back with the 49ers . . . but on the practice squad.
“Last year was a little bit of a shock getting cut and [going] to the P-squad,” McKivitz said during training camp.
“I learned the urgency of how quickly you have to learn and adapt and get better in this league or you’ll find your way out quicker than you can think.”
McKivitz refocused and went back to work. He lined up against Nick Bosa, Samson Ebukam and others while working on the scout team against the 49ers’ No. 1 defense. That experience proved beneficial.
Then, when Williams was unavailable for the 49ers’ win-or-go-home season finale against the Rams, McKivitz got the call to start the most important game of the season.
Up to that point in the season, McKivitz had not suited up for a game. Then, he received word before kickoff that Williams could not play due to an elbow injury.
“I don’t think I even had a jersey on before the game, so it was a last-minute thing," McKivitz said. "There were inklings I would be going, but it was last minute.”
The 49ers had to beat the Rams in Week 18 in order to advance to the playoffs. The 49ers trailed 17-0 before Robbie Gould hit a 42-yard field goal on the final play of the first half.
The 49ers rallied in the second half to pull out a 27-24 victory in overtime.
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“Last year was a big stage,” McKivitz said. “We [win and] get in or you lose and you’re out. This is another football game for me. It’s a chance to go out there and play the right way and play better than I did last year.”
McKivitz yielded two quarterback sacks in the game, according to Pro Football Focus, in 37 pass-blocking plays.
“I could’ve been a lot better, for sure,” McKivitz said. “I know run blocking and a couple of plays there in pass game, I always got us there. It’ll be a lot cleaner this year.”