Padraig Harrington held his nerve to win his first senior major title despite a final round charge by his Ryder Cup rival Steve Stricker in the US Senior Open.
Harrington, who became eligible for the Senior Tour last August when he turned 50, has added another milestone win to the three regular Tour majors he won in 2007-08.
He will make a triumphant return home at the start of the week to begin preparations for the Irish Open, which starts on Thursday at Mount Juliet in Kilkenny.
Having looked dialled in on Friday and Saturday, this long-awaited victory for Harrington was far from plain sailing.
Making the turn with a six shot lead, he needed to hole a series of vital putts coming in to hold off Stricker at Saucon Valley Country Club’s Old Course in Bethlehem, Pennsylvania.
"Yeah, it's tough to leave from the front, it's even tougher when it's Steve Stricker behind you, he's kind of got one up on me but maybe I owed him one today," said Harrington.
"He has certainly had my number a few times so I might have fancied another player coming up behind me, but not Steve Stricker, he tends to have one on me.
"So I was happy enough to get it done in the end.
"The USGA set up a really tough test, which is fantastic to come out and play real golf, you feel like you're under pressure out there all the time.
"It was definitely a battling week and I knew that would suit me, but it definitely put me under pressure at times."
Stricker, 55, had started the round eight shots behind Harrington.
The veteran American appeared to have played himself out of contention on Saturday when he carded a 73 while Harrington fired a 66 to give himself a six shot lead over his nearest rivals.
But while the challenge of Gene Sauers and Rob Labritz faded away over their final 18 holes, Stricker - who captained the US to Ryder Cup success at Whistling Straits last year against Harrington's European team - shot a 65 to put Harrington under massive pressure.
Realising with two holes left to play that he had a chance, Stricker birdied 17 and 18 but, ultimately, missed putts on 15 and 16 proved costly as Harrington stuttered towards the finish line.
On Saturday, the Dubliner said he had "basically given myself a lot of hands to win this" with his third round but he quickly put himself on the back foot in his final round, failing to birdie the first and then bogeying the second.
Harrington steadied the ship on the second par five, the sixth, with his first birdie of the round, gave it back again at the next only to respond with another birdie on the eight hole.
But the wheels came off a little after the turn as the Stackstown man dropped a shot on 10 and 11, the result of losing his rhythm with his putting.
The bogey on 10 was particularly frustrating for him as his attempt to drive onto or around the green saw his ball embedded in rough just above a bunker.
He took a free drop but barely advanced his ball in the rough and had to take his medicine, chipping onto the green to leave himself a long par putt that he missed.
On 11, he failed to hole a four-footer for par and he had to dig deep from there.
Harrington did just that, holing a crucial 25-footer for birdie on 15 to keep his nose in front. Stricker's big finish left him just one shot behind and, knowing the score, the Irishman coaxed a long putt down to close to the hole on 16 before making the par putt.
However while his tee shot on 17 made the green, he was left with another tricky long downhill putt and again showed mettle when left with a six-footer for par, finding the bottom of the cup to leave the final hole to negotiate.
A confident drive split the fairway on 18 and, with par enough to avoid a play-off with Stricker, Harrington put himself 30 foot from the hole with his approach and a solid putt left him with a three footer to win, which he confidently rattled into the bottom of the cup to win the big prize.
Harrington added: "It's very special.
"The reason I'm on the Champions Tour is I want to win, I want to win big events and majors on the Champions Tour.
"You might go out on the regular Tour and it's a struggle, you come here and you've got the crowd here rooting for you, rooting against you in places.
"It's why we do it and as my caddy said to me out there, 'would you want to be anywhere else', even as tough as it is coming down the stretch with a one shot lead, he kept reminding me 'would I rather be anywhere else, you would have taken this at the start of the week'."
Stricker commented: "I thought if I could get to nine or 10, and he would have had to back up, really, at the start of the day.
"I had a couple of putts on 15 and 16 I wish I could have had over, but I played well today."
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