Colts' Marlon Mack delivers 'body blows' to wear down competition

Why Cowboys and Colts can pull off upsets (1:26)

NFL Live picks the divisional-round winners and dissects why Dallas and Indianapolis both could pull off upsets. (1:26)

INDIANAPOLIS -- Indianapolis Colts coach Frank Reich likes to use a boxing analogy when it comes to his team's ability to run the ball.

"I just think it's like body blows," Reich said. "I just think it's blows to the midsection. It's the constant pounding of that. I think it wears the other team down."

Enter running back Marlon Mack.

Producing -- and showing he's a No. 1 back -- is exactly what Mack did in last weekend's wild-card playoff victory at Houston and throughout the regular season. He's coming off a Colts team record of 148 yards rushing on 24 carries against a Texans defense that had not allowed a 100-yard rusher all season. Mack had runs of 29, 26 and 25 yards and a couple of video game-type juke moves against Houston players who wore down the more Mack and the rest of the Colts' running backs ran by them in their 200-yard team performance on the ground.

"He definitely had the long speed, but I definitely saw some make-you-miss ability," Colts offensive coordinator Nick Sirianni said. "It's harder to do that if the holes aren't big. When I have seen that the most is when the offensive line is really getting movement and really displacing the windows there for Marlon to have some room to make some guys miss."

The same way the offensive line has managed to keep quarterback Andrew Luck relatively clean this season, that group also has done an exceptional job opening up running lanes. Ask any offensive lineman if they would rather impose their will in the running game or be on the defensive in pass protection, and most will likely say they prefer to run block, which suits Mack just fine.

Running behind the offensive line of center Ryan Kelly, guards Quenton Nelson and Mark Glowinski and tackles Anthony Castonzo and Braden Smith, the Colts had three games of least 200 yards rushing. Mack had five games, including the playoff game, of at least 100 yards rushing.

"It always starts up front," Sirianni said. "Like I said to those guys, it was just, 'We ride and die with our offensive line,' and they were physical, they were mean, they were nasty, they knew what to do and they started everything out, and our tight ends blocked well. Our receivers were going in there and blocking -- it truly is a full group effort when you run the ball like that."

The other fact, according to Mack, is he has managed to stay healthy after injuring a hamstring in the preseason opener in August and then missing four games during the regular season. He rushed for 908 yards despite missing those four games.

Mack also has proved he can do more than use his speed to turn the corner. He's more patient waiting for the play to develop, he can run between the tackles and he's stopped a blitzing player with a solid block in pass protection on numerous occasions.

"He's really matured as a running back," Luck said. "He's doing the little things really well, whether it's in pass protection or setting up his blockers or toting the rock, taking care of the football. He's turning into a complete back and he's running hard ... getting some extra yards. At the end of the game this past weekend, to bust a couple of those long ones -- that really felt good. I think it was a testament certainly to him and also to the guys up front blocking."

Saturday's playoff game in Kansas City (4:35 p.m. ET, NBC) screams for the Colts to run the football. An effective running game will keep Chiefs quarterback Patrick Mahomes and the high-scoring offense (35.3 points) on the sideline. The Chiefs gave up 5.0 yards a carry and 132.1 yards a game, which were 31st and 27th in the NFL, respectively, during the regular season.

The Colts are aware of those stats, but they're not basing their offensive game plan on them.

"If it's running it for 200 [yards] or throwing it for 400 [yards], I am always going to say the same thing," Reich said. "We are trying to score every time we touch the ball, and we are going to game plan and call the game in a way to score points. We are really not trying to think so much about, 'Well let's hold the ball and keep it from them.' We want to run it -- there's no secret about that. That does keep them off the field, that would be great, but at the end of the day, the primary goal is score points."