Spending a penny could cost Padraig Harrington a fortune after “the longest pee ever” led to a double bogey that saw his lead reduced to one shot in the $3.5m KitchenAid Senior PGA Championship in Dallas.

Three clear overnight, the Dubliner looked to be crushing to a comfortable 54-hole lead when he played his first 15 holes in five-under par at Fields Ranch East at PGA Frisco.

Scores

He had yet to make a bogey all week when he went to the toilet at the 16th and ran up a double-bogey six rushing back to hit his shot.

In the end, he bounced back from his first dropped shots of the week and birdied the par-five 18th for a 68 and a one-shot lead over Steve Stricker (64) on 16-under and a three-shot advantage over Stewart Cink, who had an eagle and a hole in one in a 67.

But he was upset to open the door to the chasing pack.

“Well, yeah, I let a few, I certainly could have got a low one in there today and got away from the field,” Harrington said. “Golf's like that though. It's hard to when you're leading, I don't know, the putts just didn't drop there for a while.”

He explained how he had “probably the silliest excuse ever” for hitting his sand wedge approach into the hazard at the 16th and taking two swipes to get out.

“16 came out of nowhere,” he explained. “So, essentially, I went in the toilet. The door was locked. It took me a minute to realise there wasn't somebody in there, another while to get the door open. I had, as we are on the Champions Tour, I had the longest pee ever. And then I kind of rushed down the fairway and hit my shot.

“The second shot was kind of innocuous because the pin was so tight I was just playing 15 feet left of it and to be honest, yeah, I just, I wasn't -- I do that sometimes, I just wasn't focused, I wasn't into it and I hit a bad shot in the hazard. 

“So when you get over 50, it sometimes takes a long time to have a pee. And that's my excuse. That's got to be original, I would assume.”

Despite the late drama, he still has the lead and hopes to be in the mic for his second senior Major following his US Senior Open win last year.

“Golf's a crazy game,” he said. “It's just like that. Some days you hit a bad shot and you get a break and you make birdies. Other days you play nice and solid and steady and then it just kind of gets in on you. Yeah, I would be thrilled if I turn up tomorrow and play like I played today.”

Darren Clarke shot a third consecutive 69 to share fourth place with Robert Karlsson on nine-under, seven shots behind Harrington.