INDIANAPOLIS – During those long drives through the southeast portion of the United States, Colts area scout Jamie Moore dials up SIRIUS satellite radio and tunes into the college football station.

Back in early September 2014, Moore was embarking on another season of piling up miles from campus to campus.

The radio entertainment that day had on South Florida head coach Willie Taggart.

Moore was listening to Taggart rave about a freshman starter named Marlon Mack and his 275-yard, four-touchdown debut.

"He's saying, 'I'm telling you there's something unique about (Mack),'" Moore now says about how Taggart was describing the program's eventual school-record holder.

In future stops to the University of South Florida, Moore got to know Mack pretty well.

So did the rest of college football.

Mack started all 36 games in which he played at USF, rushing for 1,000 yards each season and finishing his career as the program's all-time leader in rushing yards (3,609) and rushing touchdowns (32).

"He's an explosive guy," Moore says of Mack, who had six touchdowns travel at least 43 yards last season.

That explosion is what the Colts wanted out of their drafted running back.

Frank Gore and Robert Turbin have their own traits that have kept them in the NFL for more than 15 combined years.

But Mack provides a speed element, something the Colts were looking to add to their offense.

At South Florida, Mack's pass catching improved over his three seasons of action. He caught 65 balls during his collegiate career.

Early on in Indy, the role for Mack could be to offer a change of pace from Gore and Turbin. Down the road, more reps could come his way.

When Mack does touch the ball with the Colts, Chris Ballard and company can thank SIRIUS radio for the early introduction to their rookie runner.

"We debated back-and-forth between a couple backs (in Round Four)," Ballard said after taking Mack.

"At the end of the day, we went with Marlon just because of the speed and the explosive playmaking ability."

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