Insider: Is Marlon Mack ready to become the Colts' lead back?

INDIANAPOLIS -- The thing about Marlon Mack’s rookie campaign: It felt so boom or bust. Middle ground? It didn’t exist. He was Sammy Sosa in ’98, roping a home run one minute, striking out the next, never a single or double in sight. A 25-yard burst up the sidelines would be backed up by a six-yard loss.

His game craved consistency. So did the Indianapolis Colts’ lifeless offense.

Mack finished his rookie season second in the league in percentage of runs that went for no yards or less (32.2 percent). That’s one out of every three rushes that ended at or behind the line of scrimmage. Those are the strikeouts. The homers? He was tops in the NFL in 20-yard runs (5.4 percent of his total carries). There’s no doubt the fifth-round pick added an explosive layer to a unit that sorely needed it.

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There’s also no doubt that, moving forward, he needs to cut back on the drive-killers. The Colts can’t afford to keep facing second-and-16 or third-and-22.

Such is the expectation for a No. 1 running back in the NFL – a title Mack seeks heading into year No. 2 in Indianapolis. The South Florida product figures to, at the very least, double his usage from last fall, when the Colts gave Frank Gore 261 carries and everyone else 190. (Mack had 93.) Gore’s now in Miami. Mack’s the frontrunner to assume Gore’s old job, and lead the Colts’ dynamic, unsettled and unproven running back room in coach Frank Reich’s new offensive scheme.

“Me in this offense, I feel like I can be that explosive guy,” Mack said last week.

Maybe. But it’s never that simple. The Colts, suddenly, and somewhat surprisingly, have a stable of capable ballcarriers. There’s Mack, the rising sophomore who flashed game-breaking ability last fall but still has a ways to go on the pass-protection front. For proof: Just look up the Steelers’ game last November, when Mack’s whiffed block inside his own 10-yard line buried the Colts’ chances.

There’s Robert Turbin, Mr. Reliable, the short-yardage and goal-line master. There’s Christine Michael, somewhat of a forgotten man, the former Seattle Seahawk who tore his ACL last summer and sat out the entire season. There’s Josh Ferguson.

And there’s two intriguing rookies GM Chris Ballard scooped up in last week’s draft, North Carolina State’s Nyheim Hines and Mississippi’s Jordan Wilkins. Hines is a wide receiver-convert in the mold of Darren Sproles, a speedy open-field weapon Reich pushed the Colts hard to draft. As for Wilkins, Ballard has compared his running style to Matt Forte, the Bears’ great he helped draft while in Chicago. Each will have to prove it come training camp.

All of which makes for a crowded and competitive Colts’ running back room, something Ballard has sought at every position from the minute he arrived. While Mack remains the favorite to slide into the starting role – and assume whatever the Colts consider a No. 1 running back in 2018 – the job will eventually be decided in August. Expect a running-back-by-committee approach come the regular season.

And expect Mack to be the centerpiece.

“To me, I feel like I could have done much better (as a rookie)," Mack said. "I just made a few mistakes that I know I didn’t need (to make). Easy mistakes, so I feel like it was an okay season. I know I can do 10 times better."

Ballard, mulling over Mack’s rookie season last week in a film session with local reporters, came away largely impressed, revealing later on SiriusXM that Mack played most of the year with a torn labrum in his shoulder. Mack missed Weeks 3 and 4 with the shoulder injury but played in every game after that. After undergoing offseason surgery, he’s expected to be full-go come training camp.

“Look, everything with Marlon was better than I expected, everything,” Ballard said. “And I know he had some pass-protection issues, but he also did some good things in pass protection for a rookie back. He ran between the tackles better than I ever expected. Just because it was that outside-run (stuff), they were in that high-tempo offense, outside run-scheme – that was a hard evaluation to know if he could do it, but our scout (Jamie Moore) was driven by the kid. He kept saying he had done so much work on Marlon. You know, what his makeup was. He had played safety in high school, so he had some toughness. The coaches raved about his toughness. He said it was just kind of a byproduct of the offense.”

Where Turbin fits in remains uncertain, though it’d be foolish to downplay his value. Two years ago, Turbin’s first with the Colts, no running back in football had as many touchdowns (seven) in fewer rushing attempts (47). That’s six points ever 6.7 touches. He was also among the most efficient running backs when it came to pass-protection – an area the Colts have needed all the help they can get.

It was more of the same for Turbin last year until he injured his elbow scampering for a first down in the fourth quarter of a Monday night loss in Tennessee. Healthy by the close of the season, Turbin, 28, enters a contract year anxious to prove his worth once more.

“I don’t want to downplay Robert Turbin,” Ballard said. “Great professional. Pass pro’s great. Robert Turbin, that guy’s a pro and he’s going to be good for these young guys.”

Ballard went on to explain he loves the flavor Turbin brings to the running back room, and how his bruising style could compliment the flash of Mack, the speed of Hines and the vision of Wilkins. Keeping four running backs on the active roster, a bit unusual but far from unprecedented in today’s pass-happy NFL, remains a possibility. Reich’s Eagles did it last fall and the move paid massive dividends on their way to a world championship.

What could – and should – change things is the Colts’ revamped offensive line, starting with No. 56 at the left guard spot. Quenton Nelson will plow holes Mack’s never seen before, certainly not in the NFL. And instead of scampering to the outside – something Mack did well in 2017, but probably did too often – he’ll have far more chances to slide between the tackles. Additionally, new running backs coach Tom Rathman will drill Mack hard on his pass-protection, his most glaring and consistent weakness from 2017.

“Demanding,” Ballard called Rathman in that area.

More than anything, Ballard and Reich want one thing to stand out in the Colts’ new offense: speed. That’s why Hines was brought in. That’s why Mack will see an added load come next fall. The luxury Ballard now finds himself in: The Colts seem to have a surplus of it, a handful of capable rushers that will offer a level of depth to the position this team hasn’t enjoyed in years.

The days of Trent Richardson and Boom Herron and Josh Robinson are over. Frank Gore’s in Miami. Is it Marlon Mack’s time?

“I always think about putting speed on our turf,” Ballard added last week. “To me, that matters – you build your team around where you’re playing most of your games at.”

Colts claim tight end: The Colts claimed tight end Randall Telfer off waivers from the Kansas City Chiefs, waiving tight end Jason Vander Laan. Telfer started 14 games for Cleveland last season, playing 299 offensive snaps, and was traded to Kansas City in the offseason. Telfer had 5 catches for 40 yards in his two seasons.

Call Star reporter Zak Keefer at (317) 444-6134 and follow him on Twitter: @zkeefer.