PROVO, Utah – For the second time this season, BYU football has lost its leading rusher to a season-ending ACL injury.

This time its redshirt freshman running back Sione Finau. Multiple sources tell KSL Sports that Finau injured his ACL during practice Tuesday. The injury will sideline Finau for the remainder of the season. No timetable has been given for how long Finau is expected to be out beyond the 2019 season.

Finau, a former prep standout locally at Kearns High School, emerged as a go-to back in BYU’s offense last month in the Cougars’ rivalry victory against Boise State. He rushed for 89 yards in the upset.

Since the Boise game, Finau has become BYU’s leading rusher, compiling 359 rushing yards and a career-high 102 yards against Idaho State on Saturday.

BYU officials were unable to confirm the status of the injury, or when they expected Finau to return.

Sione Finau continues to get better every week. Second touchdown run of his #BYU career. With Katoa injured, Finau is the clear-cut No. 1 back right now. BYU leads 21-3.#BYUfootball #KSLsports — Mitch Harper (@Mitch_Harper) November 16, 2019

Up until BYU’s win over Idaho State last week, Ty’Son Williams was BYU’s leading rusher this season.

Williams, a graduate transfer from the University of South Carolina, rushed for 264 yards in four games played. He injured his ACL in BYU’s loss against Washington back in September.

Where does BYU go from here at running back?

There are a lot of questions surrounding BYU’s running backs heading into the UMass game (Saturday, 10 a.m. on KSL Newsradio).

Without Finau, BYU will hope to have Lopini Katoa ready against the Minutemen. Katoa missed Saturday’s game against Idaho State as he was being monitored in the team’s protocol.

He was seen in his practice jersey and pads walking out of the Indoor Practice Facility Tuesday night, but no official word has been announced if he has cleared protocol or not.

Fans are going to get more familiar with RB Jackson McChesney next year in this #BYU offense. He had interest/offers from Big Ten programs coming out of Lone Peak, but was always committed to BYU. #BYUFootball #KSLsports — Mitch Harper (@Mitch_Harper) November 16, 2019

Graduate transfer Emmanuel Esukpa started last week against Idaho State, but was sidelined shortly after the first series. In his postgame comments, head coach Kalani Sitake said Esukpa still wasn’t 100 percent, as he continues to recover from a foot injury he suffered against USF.

Esukpa’s status and availability for UMass were not known.

That leaves true freshman Jackson McChesney, who made his first appearance in the win over Idaho State last week. McChesney, a former three-star recruit from Lone Peak High School, ran for 46 yards on 10 carries in his collegiate debut against the Bengals. McChesney is one of the fastest players in BYU’s program.

After McChesney, BYU also has walk-on junior college transfer Alec Wyble-Meza and returned missionary walk-on Chase Wester in the backfield.

Mitch Harper is a BYU Insider for KSLsports.com and host of the Cougar Tracks Podcast and Cougar Sports Saturday (Saturday from 12-3 pm) on KSL Newsradio. Follow him on Twitter: @Mitch_Harper.