Why the 49ers Should Keep Jordan Mason Instead of Trey Sermon

The 49ers have a big decision to make.

Will they keep running back Trey Sermon, whom they traded up to draft in Round 3 last year, or Jordan Mason, an undrafted rookie free agent? Normally, this would be a no-brainer -- keep the third-round pick. But through two preseason games, Sermon is averaging just 1.7 yards per carry, while Mason is averaging a whopping 5.8 yards per carry.

Let's take a play-by-play look at what each running back did against the Vikings.

Trey Sermon

1. 10:45 1st Quarter. 1st and 10 at the Vikings 48. Sermon runs to his right, hesitates in the backfield and tiptoes into the hole with no power or violence for a gain of just two yards.

2. 6:11 1st Quarter. 1st and 15 at the 49ers 30. Sermon gets a pitch to his right, sprints to the outside, cuts upfield, gets stood up and knocked backward after a gain of just one.

3. 1:47 1st Quarter. 1st and 10 at the Vikings 41. Sermon starts by running between the tackles, but quickly bounces outside to his right, gets hit and knocked backward after a gain of three.

4. 0:22 1st Quarter. 4th and 3 at the Vikings 34. Sermon runs a Texas route from the backfield and is open, but he spots a safety nearby, alligator arms the pass and drops it.

5. 12:45 2nd Quarter. 1st and 10 at the 49ers 20. Sermon runs to his left, bounces to the outside, lowers his shoulder and gets knocked out of bounds after a gain of three.

6. 11:11 2nd Quarter. 1st and 10 at the Vikings 34. Sermons runs up the gut, gets hit immediately by a safety, who gets underneath Sermon's bads and drives him onto his back after a loss of one.

7. 10:26 2nd Quarter. 2nd and 11 at the Vikings 35. Sermon lines up outside like a wide receiver and runs a curl route against a cornerback -- the 49ers are trying to get him in space against a smaller player. So far, so good. Sermon runs a quick curl route, and the cornerback hits him, wraps him up and throws him backward after a gain of just four. Sermon needs to run harder and finish his runs with violence.

Jordan Mason

1. 13:56 4th Quarter. 1st and 10 at the 49ers 28. Mason runs to his right bursts around the edge, gets hit and falls forward for a gain of 7.

2. 12:32 4th Quarter. 1st and 10 at the 49ers 45. Mason runs up the gut to the left, cuts back behind the right tackle, breaks two tackles and gains four yards.

3. 11:53 4th Quarter. 2nd and 6 at the 49ers 49. Mason runs up the gut to the right, spots a cutback lane to the left, gets hit at the line of scrimmage and falls forward for a gain of three.

4. 8:26 4th Quarter. 1st and 10 at the Vikings 37. Mason runs to his left, gets hit in the backfield and powers forward for three yards.

5. 6:58 4th Quarter. 3rd and 1 at the Vikings 28. Mason runs up the gut to the left, spots a small crease between the left tackle and the left guard and powers through it for a gain of two and a first down.

6. 5:27 4th Quarter. 2nd and 6 at the Vikings 22. Mason runs up the gut to his right, cuts back behind the left tackle, breaks four tackles and finally gets dragged down after a gain of 17.

7. 4:41 4th Quarter. 1st and goal at the 5. Mason runs up the gut to the right, cuts all the way back behind the tight end and scores untouched, but the play doesn't count because Tanner Hudson committed a holding penalty.

8. 2:31 4th Quarter. 1st and 10 at the 49ers 4. Mason runs up the gut to the left, has nowhere to go, bounces outside, makes one cut and plows upfield for a gain of five.

9. 2:00 4th Quarter. 2nd and 5 at the 49ers 9. Mason sprints to his right, turns the corner and dives forward for six yards.

10. 1:15 4th Quarter. 1st and 10 at the 49ers 15. Mason sprints to his left, turns the corner, breaks four tackles, lowers his shoulder and falls forward through a tackler to gain 10 yards and ice the game.

Mason clearly is faster, stronger, more powerful, more decisive and just plain better than Sermon at this time. If the 49ers have to keep one, they should keep Mason even though they didn't draft him.