Marlon Mack, Frank Gore's Fantasy Outlook After Week 5

Marlon Mack—and not Frank Gore—was the running back to save the Indianapolis Colts from a loss to the winless San Francisco 49ers on Sunday.

Mack finished with a game-high 91 rushing yards and a touchdown on nine carries in the 26-23 overtime victory, while Gore tallied just 48 yards and zero scores on 14 carries. To Gore's credit, he was the more effective back in the passing attack with three catches for 38 yards on four targets compared to Mack's one catch for two yards.

Even with Gore's receiving yards, Mack gave fantasy football players something to think about when analyzing the Colts backfield. With that in mind, here is a fantasy breakdown for each.

Marlon Mack

The rookie from South Florida turned heads Sunday, as Bleacher Report's Matt Miller called him "good" and pointed out he is "fulfilling a lot of pre-draft predictions."

Mack proved fruitful to fantasy players because of his 22-yard touchdown, but he demonstrated burst in the open field with a 35-yard run as well. Those are the types of game-changing plays that will earn him more playing time, especially since Gore is 34 years old with plenty of miles on his legs.

Exercise caution with Mack, though, seeing how he had minus-three rushing yards the last time he registered stats in a game (Sept. 17 against the Arizona Cardinals) and tallied just 24 yards on 10 carries in the season-opening loss to the Los Angeles Rams. He also hasn't been a threat in the passing game (three catches), although he demonstrated he can be with 28 receptions in his final year at South Florida.

For now, Mack is worth a waiver-wire pickup with the hope his marquee showing Sunday will generate additional opportunity. Wait before inserting him into your starting lineup until there is more of a track record to trust.

Frank Gore

It feels irresponsible to doubt the five-time Pro Bowler, especially given his durability after appearing in all 16 games in each of the last six seasons.

He has also been nothing but consistent in the stat books with nine seasons of more than 1,000 rushing yards and zero seasons with less than 853 since he was a rookie back in 2005. Gore has also been a reliable piece of Indianapolis' passing game with 38 catches last year and 34 in 2015.

With all that being said, it is fair to at least wonder about his long-term effectiveness at this stage of his career. He is yet to top 57 yards on the ground in any of the Colts' first five games, and he has just two touchdowns.

If there were ever a time for a youngster to carve out regular playing time in the Colts backfield, it is now. The 2-3 Colts also don't figure to be leading many games where they will turn to the ground attack to work the clock considering their two victories are against the winless 49ers and Cleveland Browns.

Don't make any drastic moves like cutting Gore based on his consistent success throughout his career, but hesitate to start him moving forward.