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Colts running back Marlon Mack practices, must be cleared by neurologist to play Sunday

INDIANAPOLIS, IN - OCTOBER 21: Marlon Mack #25 of the Indianapolis Colts runs for a touchdown in the 37-5 win against the Buffalo Bills at Lucas Oil Stadium on October 21, 2018 in Indianapolis, Indiana. (Photo by Andy Lyons/Getty Images)

INDIANAPOLIS, Ind. – The Indianapolis Colts find themselves in a two-for-two injury situation heading to Jacksonville, but it’s the status of a third player that might command the most attention.

Marlon Mack was a full participant for a second straight practice Friday, but the second-year running back still must gain clearance from an independent neurologist to play against the Jaguars. He remains in the NFL’s concussion protocol after suffering a concussion in the fourth quarter of last Sunday’s win over Miami.

Is Frank Reich optimistic the team’s leading rusher will be available?

“Those things, I’ve said yes before and been wrong, so I’m going to hold any judgment on that with him,” he said.

Also on the injury front, center Ryan Kelly (knee) and tight end Mo Alie-Cox (ankle) have been ruled out. Their absence is countered by the anticipated return of tight end Erik Swoope (knee) and offensive lineman Joe Haeg (ankle).

The Colts are activating Haeg off of the injured reserve list, where he’s been since suffering a sprained left ankle Sept. 23 at Philadelphia.

“It’s been a long time and I’m looking forward to getting back into it,” he said. “Just to be able to go back out there and help these guys out any way I can is awesome.”

Haeg started at left tackle in the season opener and at right tackle in weeks 2-3, but his likely role moving forward will that of invaluable backup. The 2016 fifth-round pick has started 32 games at three positions the past three seasons.

Haeg hasn’t started or played in a regular-season game at center, but that was a position he concentrated on during the offseason. With Kelly down at least one more game, Haeg probably represents the main backup to Evan Boehm.

Swoope remains questionable for the Jacksonville game, but the Colts desperately need his contributions after Pro Bowl tight end Jack Doyle suffered a season-ending kidney injury against Miami.

“I still have to be sure I’m physically ready to go, but we understand this tight end room is very productive,” Swoope said.

The Colts ends have combined for an NFL-high 18 touchdowns and rank second with 83 receptions. The breakdown of the 18 TDs: Eric Ebron 11, Swoope 3, Doyle 2, Cox 2.

Swoope has been productive when he’s been on the field, catching 7 passes for 83 yards and a career-high 3 TDs. However, he’s been limited to five games and two starts.

“It’s going good,” he said of his return. “Anytime you’re coming back from something there’s going to be a sense of making sure everything feels good and you’re just trusting your body is going to do what it can.

“I’m optimistic . . . optimistically optimistic.”

Mack’s value

The importance of Mack’s availability can’t be overstated.

In the four games he’s missed, the Colts’ ground game has averaged 67 yards per game and 3.7 yards per attempt. With Mack in the backfield, the numbers balloon to 139.1 yards per game and 4.8 per attempt.

In his seven games, Mack has averaged 79.4 yards per game and 5.1 yards per attempt. He posted his two 100-yard rushing games in consecutive games against Buffalo (126) and Oakland (132).

You can follow Mike Chappell on Twitter at @mchappell51

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