When St. Thomas Academy was shut out in the regular-season finale by Chaska, its only loss of the season, coach Dan O'Brien found a silver lining.

"You hate to ever say a loss was a good thing, but in that particular case, it helped us a little bit," O'Brien said. "We were able to refocus and go back to the drawing board."

The refocused Cadets delivered their best offensive showing of the season in a 53-16 romp over Elk River in a Class 5A semifinal Saturday at U.S. Bank Stadium.

St. Thomas Academy had five touchdowns of 32 yards or longer and 499 yards of total offense. Running back Danny McFadden had 216 total yards — 129 rushing, 87 receiving — and scored three touchdowns on just 13 touches.

The best part, as far as the Cadets were concerned, was earning a Prep Bowl rematch with Chaska.

"That was huge motivation for us," quarterback Joe Deyak said.

The Cadets rarely seemed fazed by the Elks' now-trendy straight-T offense, a quick-hitting, three-headed rushing attack rooted in misdirection. They routinely stopped the dive play up the middle and showed enough discipline to disregard the fakes that so often fool opponents.

Elk River, which averaged more than 430 yards rushing per game, was held to 182 on the ground. Things were so lopsided that the fourth quarter was played on running time.

"We played a better team today," Elk River coach Steve Hamilton said. "We kind of felt that going in. They were pretty physical and really good up front."

On the Cadets' second possession, McFadden darted through the left side of the line and outraced the Elk River defense for a 32-yard touchdown. A successful two-point conversion gave them an 8-0 lead.

Elk River put together a classic Elks 52-yard scoring march to tie the score 8-8 soon after when Joe Nordstrom ran 11 yards for a score. But that was all the Elks could muster until scoring a late fourth-quarter touchdown.

St. Thomas Academy quickly responded with a 66-yard drive that ended in a 3-yard scoring run by Love Adebayo.

A short McFadden touchdown run just before halftime made the score 24-8 at the break.

In the Cadets' explosive third quarter, the offense scored touchdowns on its first two possessions. First McFadden scored for the third time with a 47-yard run one play after the St. Thomas Academy defense stopped Elk River on downs at midfield. Soon after, Cadets quarterback Joe Deyak got in on the scoring with a 67-yard run.

"It was definitely our best game," McFadden said.