Sep 7, 2025; Seattle, Washington, USA; San Francisco 49ers general manager John Lynch watches pregame warmups against the Seattle Seahawks at Lumen Field. Mandatory Credit: Joe Nicholson-Imagn Images Joe Nicholson-Imagn Images

The Ideal Backup QB if Mac Jones Leaves the 49ers This Offseason

Originally posted on San Francisco 49ers on SI
By Henry Cheal | Last updated Feb 18, 2026 9:00 AM ET

The San Francisco 49ers will likely be prepared to receive multiple trade offers for backup quarterback Mac Jones this offseason.

Jones being pursued elsewhere as a potential franchise quarterback is well deserved. He went 5–3 as the starter while Brock Purdy was sidelined with turf toe, a stretch that helped the 49ers secure a playoff berth.

Though the 49ers’ stance is that they want to keep him for a second year under the terms of his team-friendly two-year, $7 million contract, Jones could still be moved for the right draft pick.

However, he should not go. He is too valuable, and the 49ers have clearly helped him play some of the best football of his career. You never know, he could end up starting multiple games in red and gold again in 2026.

But if the 49ers do let him go, a strong candidate could emerge as a possible replacement in free agency. Contingency plans are necessary.

Marcus Mariota could be a possible solution if Mac Jones departs

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Marcus Mariota is set to enter free agency after two seasons with the Washington Commanders.

In 2025, he became especially important when Jayden Daniels battled injuries for much of the season. Mariota stepped up, throwing 10 touchdowns and finishing with an 86.1 passer rating.

If Jones does leave, Mariota could be a sensible backup target given his experience. In head coach Kyle Shanahan’s system, he could elevate his play further. Shanahan has a history of revitalizing former high draft picks in backup roles.

Just look at Sam Darnold. After rebuilding his value, he later joined the 49ers’ divisional rival, the Seattle Seahawks, and went on to win a Super Bowl.

Pro Football Focus ranks Mariota fifth on the NFL's quarterback free agent rankings, stating: "Mariota played a larger role than anticipated this season, filling in for Washington as Jayden Daniels dealt with multiple injuries. The 32-year-old earned a 72.3 PFF passing grade with a 6.9% big-time throw rate, though he also recorded a 4.2% turnover-worthy play rate. Mariota's skill set and experience align well with either another backup role or a short-term starting opportunity in 2026."

It would be wise to explore the market if it begins to look like Jones could leave at any point. There are several intriguing quarterback options available, though the 49ers can safely rule out a reunion with Jimmy Garoppolo and the near-impossible scenario of Aaron Rodgers joining.

Even if it’s just a one-year deal, he could be a possible option. But Mariota isn’t likely to start anywhere in the league, so the 49ers face little risk of losing him as long as he remains competent in his role.