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INDIANAPOLIS – Marlon Mack’s worst fear has been confirmed.

A magnetic resonance imaging (MRI) test revealed the Indianapolis Colts’ feature running back suffered a torn right Achilles tendon in Sunday’s opening 27-20 loss at Jacksonville Surgery is required, which will end his season and perhaps his career with the team.

Mack, 24, is in the final year of his rookie contract. He had hoped to receive an extension during the offseason, but that never occurred. Now, the 2017 fourth-round pick faces an uncertain future – free agency and coming back from a serious injury.

Prior to suffering the Achilles injury on a 3-yard reception in the second quarter, Mack had rushed four times for 26 yards and caught three passes for 30 yards.

In 41 career games, Mack has rushed 2,383 yards on 539 attempts.

Without Mack, the Colts must lean on rookie Jonathan Taylor, Nyheim Hines and Jordan Wilkins.

At Jacksonville, Hines led the team with 28 yards on season carries while Taylor added 22 yards on nine attempts. Hines added a team-high eight receptions for 45 yards and Taylor 67 yards on six catches.

You can follow Mike Chappell on Twitter at @mchappell51.

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