Not just any U.S. Amateur, either. It was the one in which a celebrated Stanford freshman named Tiger Woods struggled to shake off Mark Plummer, the stocky Mainer with the unorthodox swing, in a semifinal slugfest at Newport (R.I.) Country Club. Hayes’ father was on the medical staff.

Two decades later, grown-up Hayes and ageless Plummer — two ginger-haired golfers, two generations apart — will go head-to-head for their state championship.

Hayes, 25, leads Plummer, 63, by two strokes after Wednesday’s second round of the 96th Maine Amateur at Waterville Country Club. He maintained the lead with a 1-under 69 for a two-day total of 134.

“I don’t remember Mark, but I remember watching Tiger finish the 18th hole. I had a couple glimpses of it,” Hayes, whose family lives in Cape Elizabeth and Newport, R.I., said. “It’s cool how it’s come full circle. I’m stoked to play with him tomorrow. He’s a legend in Maine golf. It’s cool that he’s been around so long. And he’s such a great guy. He’s always been nice to me.”

Maybe, but the rivalry was on when Plummer, who trailed by four shots to start, briefly took the lead on Wednesday’s back nine.

Plummer last won the tournament in 2002, hasn’t been a runner-up since 2008 and didn’t even play in it a year ago. Just in case anyone dared think Tuesday’s 69 was an aberration, Plummer started his encore with three consecutive birdies, the springboard to a 3-under 67 that cut Hayes’ lead in half.

“The first amateur I played in here was 1969. That’s a long time between tournaments,” Plummer said with a laugh. “I didn’t know what expect. I’ve been playing fairly well, but that doesn’t necessarily translate to playing well in the tournament.”

Sam Grindle of Deer Isle is the only spoiler within shouting distance. He’s at 139, five shots back, after an even-par 70. It would take a sizzling round and an utter collapse by the entire lead group for 2014 runner-up Joe Walp (142) or three-time winner Ricky Jones (143) to crash the party.

Wednesday had the feel of a championship round. Plummer and Hayes played in back-to-back threesomes with lunch-hour tee times. They were tied at 5-under at the turn.

Hayes rode out a six-hole stretch in which he didn’t register a single par. Bogeys on 6, 7 and 8 brought him back to Plummer, and another bogey on 10 canceled out a birdie at 9.

“Ten was a stupid bogey,” Hayes said. “I was 1-over at the time. Then on 11, I hit a really good approach shot to about two feet and made the putt. That definitely changed the round. I’m really glad I got it under par. It was a big grind out there.”

It was an uneventful finish for Hayes, with only a birdie at 15 interrupting his parade of pars down the stretch.

Plummer bogeyed the par-3 13th for the second consecutive day to restore Hayes’ lead. He also made bogey at 16 before a birdie at 17 and an adventurous short par putt at 18 closed it out.

“Both the long par-3s on the back nine I made bogey. Missed the green on both of them,” Plummer said. “I made a nice birdie on 17 with a wedge to about 15 feet. Thought I’d made birdie on 18. Then I thought I’d missed the second one, so I guess it evened out.”

Grindle exploded from the gate. He carded birdie at 2 and eagle at 3 to go 4-under. With a shorter tee box in effect for the second round, Grindle used a driver to cut off the dogleg to the 480-yard third hole and stuck his approach shot to 12 feet.

He carded only one birdie thereafter, on 12, against four bogeys.

“I started hot again, 3-under through three. Then I kind of played a little conservative. I wish I could have a few shots back,” Grindle said. “Some of the putts, I had a few downhillers that just weren’t as quick as I thought they would be. I was just afraid playing in the afternoon that it would be a little drier, a little quicker.”

Hayes showed no signs of slowing down early, with birdies at 3 and 4 advancing him to 7-under.

Plummer bagged another birdie at 7 and played a bogey-free front nine while Hayes struggled to regain his first-round form.

“It was a struggle,” Hayes said. “I’m not complaining, obviously, but it was birdie, bogey, birdie, bogey. I was fortunate to get it back.”

Aside from Hayes and Plummer, Malcolm Oliver (68) of Damariscotta and Luke Ruffing (69) of Manchester shot the only subpar rounds of the day.

Oliver is tied for sixth with Lowell Watson at 144. Ruffing is knotted with Mike Doran for ninth at 146.

Two triple bogeys relegated defending champion Andrew Slattery of West Minot to 77 and a two-day aggregate of 149. He is tied with Chris Cloutier of Lewiston and Auburn native Curt Jordan.

Joe Baker (150) of Oxford and Brian Bilodeau (151) of Auburn also made the cut, which was 12-over. Forty-six golfers will play the final round.

Hayes’ best previous finish in the tournament was a tie for fifth at Sunday River in 2012.

“Mark’s probably the best putter ever to come out of Maine. He’s just unbelievable on the greens,” Hayes said. “It’s probably going to take 2-under or better, depending on how he plays and Grindle plays. Hopefully I can get it going (Thursday).”

Waterville, like Plummer’s home layout at Augusta Country Club, is a Donald Ross course designed a century ago. Perhaps it is no surprise that it has proven such a perfect fit for such an enduring player.

“The greens and length of the golf course are very similar. It feels a lot like playing at home,” Plummer said.

“I’ve been stuck on 13 (titles) for a long time. I’ll kind of go hole-by-hole and see how things go.”

Much the same way he once tried to tame a Tiger, while a wide-eyed little boy named Johnny looked on.

koakes@sunjournal.com