49ers running back Jordan Mason is making the most of his last-minute promotion.

Mason got the start Monday night against the Jets after Christian McCaffrey was placed on the inactive list with calf and Achilles injuries. He ran 17 times for 88 yards, with the last five of those yards taking him to the end zone for the fifth time in his career.

The touchdown capped a 7:18 drive early in the second half that put the 49ers ahead 16-7.

Wide receiver Jauan Jennings was forced to leave the game during the scoring drive with what appeared to be a leg injury. He was tackled by Jets cornerback Michael Carter after gaining five yards in what appeared to be the type of hip-drop tackle the league banned this offseason. Carter was not penalized, but he could face a fine this week.