Jordan Mason within sight of breaking 49ers franchise record that has stood for nearly quarter of a century

There's a chance that Thursday's game with the Seattle Seahawks is Jordan Mason's last start at running back for the San Francisco 49ers before Christian McCaffrey returns to the fray.

McCaffrey is said to at least have a shot of returning in Week 7 against the Kansas City Chiefs having not played so far this season because of Achilles tendinitis.

But it will be Mason leading the way in the backfield again in primetime in a crucial NFC West clash, and he has the chance to break a 49er record that has stood since 2000.

Mason has already broken McCaffrey's record for the most rushing yards in the first five games to start a season, having racked up 536 to this point.

With 74 rushing yards against Seattle, Mason will break Charlie Garner's record for the most by a 49er across the first six games of a season. Garner rushed for 609 yards in the first six games of the 2000 season for the Niners, eventually finishing with 1,142. That was Garner's second and final year with the 49ers and he finished with over 1,000 yards in both.

Mason already has three 100-yard games this season, his worst performance seeing him record 77 yards on the ground.

As such, he will be confident of making more franchise history against a Seattle defense that is 27th in success rate against the run across its last two games, defeats to the Detroit Lions and New York Giants. The Seahawks are injury hit on the defensive side of the ball, with rookie defensive tackle Byron Murphy II among their absences for Week 6 . Seattle's top pick is set to miss a third straight game.

McCaffrey's prospective return may dash Mason's hopes of reaching 1,000 yards this season. However, Mason has already built a very strong argument for the 49ers using him as part of a one-two punch with McCaffrey when the latter returns, rather than having the reigning Offensive Player of the Year dominate the workload as he did last year.

That case will get even stronger if he produces a history-making display in Seattle that helps the 2-3 49ers get back on track.

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