COLUMBUS — It’s been 18 years and Greg Frey still refuses to accept defeat.

‘‘There were 2 1/2 minutes left on the clock, and now we’ll never know,’’ the former Ohio State quarterback said Monday.

When No. 1 Southern California hosts No. 5 Ohio State on Saturday in the first big tilt of the college football season, it will be the first time the teams meet since their showdown in 1990, — a game people still talk about because of its bizarre circumstances and twist at the end.

No. 18 USC marched into Ohio Stadium to take on the 15th-ranked Buckeyes before a raucous crowd of 89,422 and a national television audience on ABC. The Buckeyes were 2-0 and had permitted just 126 yards on the ground in those two victories. Coach Larry Smith, an Ohio native, and his Trojans were 2-1 and had plummeted 13 spots in the rankings after getting drilled 31-0 at Washington the week before.

The scene was set for some Big Ten redemption. After all, USC had broken a lot of Buckeyes’ hearts with victories in the four previous meetings. A year earlier, the Trojans won 42-3 in Los Angeles. And one-point losses in the Rose Bowl to USC had cost Ohio State shots at national titles in 1974 and again in 1979.

In 1990, the Trojans dominated right from the start. Zuri Hector returned a blocked punt 8 yards for a touchdown and tailback Ricky Ervins went 15 yards for a TD — part of an eye-popping day featuring 199 yards on 28 carries with two TDs — for a 14-0 lead after a quarter.

USC stretched its lead to 28-10 midway through the third quarter on Scott Lockwood’s 66-yard run. At about the same time, a thunderstorm swept in and put on a horizon-to-horizon light show. Lightning and thunder rocked the old concrete stadium, and a squall brought a downpour.

And still they played on.

‘‘We were concerned about the fans and the teams,’’ then-Ohio State athletic director Jim Jones said. ‘‘When you think about it, we were at the mercy of God in the whole scheme of things.’’

The Buckeyes drove 50 yards through the thunderstorm for a touchdown on Raymont Harris’s 1-yard run and Frey’s two-point conversion pass to Jeff Graham. That left the Trojans on top 35-26 with 2:36 left.

‘‘I’ve been involved with a lot of comebacks but that was awesome because of the conditions,’’ Frey said. ‘‘So we had some momentum. I had been down this road before. I’m thinking, ’We’ve got a ton of time.’’’

Except they didn’t.

Referee Ron Winter conferred for a second time with USC’s Smith and Ohio State coach John Cooper about suspending the game. ADs Jones and Mike McGee of USC were not a part of the talks.

‘‘I told him we were going to try an onside kick,’’ Cooper said in the humid postgame interview area. ‘‘I told him if USC gets it, it’s all over.’’

And that’s precisely what happened. Tim Williams’ kick was smothered by USC reserve safety Bruce Luizzi. The officials grabbed the ball and left the field and the teams ran into the locker rooms to get out of the storm.

‘‘When you’re playing, usually when you see lightning you know the game could be over at that moment,’’ Ervins recalled in between shots at a golf outing on Monday. ‘‘All of a sudden those crazy lightning bolts were coming through hard. So, they told us to take shelter and we ran off the field. Before you know it, they told us the game was over.’’

No one was happier than Ervins’ backup, Mazio Royster, who had seven carries for 70 yards including one long run that he thought might be his last.

‘‘Beautiful,’’ he said of the decision to call the game. ‘‘I was ready to get the hell out of there because it was a scary sight. I couldn’t wait to get back and see my 50-yard run and I was hoping the Lord would bless me and I could make it.’’

Outside the Trojans’ locker room, Smith shrugged his shoulders and with a sly smile and said he told Cooper: ‘‘Hey, I’m ahead. If you want to call it now, it’s fine with me.’’

Making the situation even worse for distraught Ohio State fans, no sooner had the teams left the sodden field — and the wet, angry fans had filed out of the stadium — than the weather cleared.

The fallout was almost immediate. Ohio State’s fans were outraged that Cooper elected to take the defeat instead of taking a chance on an improbable but not impossible rally. Cooper had never been popular since taking over in the wake of a messy coup d’etat when Earle Bruce was fired three years earlier. But now his critics were calling him a quitter, a tag he had difficulty avoiding.

USC completed an uneven 8-4-1 season that included a second-place finish in the Pac-10 and a loss to Big Ten member Michigan State in the John Hancock Bowl.

The shell-shocked Buckeyes turned around and lost the next week to Illinois at home, then tied Indiana. They ended up 7-4-1, winding up in dismal fashion by losing to rival Michigan at home and then getting embarrassed by overmatched and undermanned Air Force in the Liberty Bowl.

Cooper survived not only the USC debacle, but even those painful losses at the end of the season, to continue as Ohio State’s coach for another decade.

The years have not smoothed the rough edges off such a bitter defeat for Frey, now a successful businessman and high school assistant coach in Columbus.

Asked what he remembers most about that dark and dangerous Saturday, he said sarcastically: ‘‘The end of it, obviously. Or the lack thereof.’’