Taysom Hill and BYU didn't have much trouble getting by Utah State last October after Aggies quarterback Chuckie Keeton went down with what proved to be a season-ending torn ACL.
An injury to the same knee will keep Keeton out of Friday night's showdown in Provo.
With both teams coming off byes, the 18th-ranked Cougars try to stay unbeaten and continue their recent domination of Utah State.
BYU (4-0) has taken three straight and 13 of 14 in this in-state series after winning 31-14 on the road last Oct. 4. Hill threw for 278 yards and three touchdowns while Utah State lost Keeton in the first quarter.
The Aggies (2-2) will again have to get by without Keeton, who is dealing with an injury to the same knee and could be done for the season. He was hurt against Wake Forest on Sept. 13 and missed a 21-14 overtime loss at Arkansas State the following week.
"Chuckie's ability to create and his leadership and his experience, certainly you have to acknowledge," Cougars coach Bronco Mendenhall said. "But really by preparing for him, anything else besides that you're kind of ready for."
Keeton's absence could make things all the more difficult for Utah State, which hasn't won in Provo since 1978. The Aggies have dropped each of their last 17 visits, though the last two were both decided by three points.
"It's a tough place to play. LaVell Edwards Stadium has been a major home-field advantage for them over many, many years," Aggies coach Matt Wells said. "They play well at home. We have a tremendous challenge on our hands.
"They're playing very well, and they're hot right now. They have one of the hottest quarterbacks in the country. They're always stout on defense. I already know that. I've seen that, and you know it from all the years playing them."
The Cougars, averaging 37.5 points, are enjoying their best start since opening 6-0 in 2008. Hill threw for two touchdowns and added another on the ground as BYU beat Virgina 41-33 on Sept. 20.
"I think they battled really well," said Mendenhall, whose team trailed 16-13 at halftime. "You could tell it was different for us from the beginning of the game. It was an appropriate and necessary situation to learn from and we put ourselves in it and we showed ourselves what we could do."
Hill is tied for first in the country among QBs with seven rushing TDs, and his 107.0 yards per game rank third. While the Cougars are averaging an impressive 230.3 yards on the ground, they could face a stiff test against an Aggies defense surrendering just 78.3 per game - tied with Michigan State for fourth in the FBS.
Utah State took a 14-7 lead into halftime at Arkansas State but couldn't keep up down the stretch with Keeton on the sidelines. Darell Garretson completed 27 of 46 passes for 268 yards with two touchdowns and an interception.
"You ask if there's concern, yes, there is. But all of our goals, everything that we want to achieve this year as far as the Mountain West is concerned and our bowls are right in front of us," Wells said. "You're hurt and you're crushed because you missed an opportunity to beat a really good team on the road and get to win number three."
The Aggies, who also suffered a season-opening 38-7 loss at Tennessee on Aug. 31, have dropped six straight and 25 of 26 road games against non-conference foes.
However, Utah State has won two of its last three matchups against ranked teams, including a 21-14 victory over No. 24 Northern Illinois in last season's Poinsettia Bowl.