Certainty is a dangerous emotion in golfing context. Which does not stop it appearing. As Jordan Spieth converted for 20ft for an eagle at Royal Birkdale’s 15th, his Open lead stretched to three, everyone else was expected to play for second. Spieth was odds-on to prevail.

On a day which showed how the elements can reduce the world’s best golfers to quivering wrecks and a stoppage was necessary because of flooded greens, the Weatherman had emphasised how a nickname earned in college was as apt in his professional pomp.

Jordan Spieth weathers the storm to secure a two-shot lead in the Open | Andy Bull Read more

Within one hole, an untidy bogey had narrowed Spieth’s margin for error. His advantage was still two at close of play, Matt Kuchar the 23-year-old’s closest challenger. Spieth gave himself a “B grade” for Friday’s 69; at one point, others were handing him the trophy that narrowly eluded him in 2015.

“Anytime you’re in the last group on a weekend in the major, and this is, I think probably a dozen times I’ve had at least a share of the lead in a major championship, you get nervous,” said Spieth, who is now six under. I’ll be feeling it this weekend a bit. But I enjoy it because as long as I approach it positively and recognise that this is what you want to feel because you’re in a position you want to be in, then the easier it is to hit solid shots and to create solid rounds. So I feel good now.”

The note of caution to pretenders is thus: on the other two occasions Spieth has opened majors with successive rounds in the 60s, he has won. “My game is close,” he warned. “It is very close.” Heaven help us when it reaches a peak.

Kuchar forms part of a tantalising leaderboard which contains a multitude of stories, from those in pursuit of a maiden major to Brooks Koepka, seeking a second in as many appearances. Koepka shares three under with Ian Poulter.

Home support continues to pull – loudly – for Poulter. Even those in the stands might have given up hope of the 41-year-old ever winning a major long ago but, crucially and typically, the man himself did not. As others faltered in the worst of round two conditions, Poulter held firm. His level par 70 maintained position at minus three.

“It feels absolutely marvellous, it really does,” said Poulter. “Walking up 18, just walking from all greens to tees was really pretty special today. Huge galleries and they were really pulling for me. So it was really nice to be in position, keep churning out decent scores and keeping myself on the board. It was great.”

This should not be interpreted as Poulter lacking competitive fire. He is here to win. Golf’s propensity for fairytale means he may well.

Bookmakers tell the story of Rory McIlroy’s Open. He wore a broad grin when insisting on Wednesday that he was worth a pre-tournament wager at 20-1. Inside six first-round holes, that price had multiplied 10-fold. By the time he posted a Friday 68 for a one-under total, McIlroy was back amongst the favourites.

Whatever McIlroy adjusted – technically or by way of attitude – after that extraordinary start, it has transformed his game and may yet do likewise for his season. The key question is whether or not he can afford to give Spieth such a head start.

“I set myself a target of being in a better position today than I was yesterday,” McIlroy explained. “I wanted to be at least level par or under par if possible for the championship and I’ve been able to achieve that goal that I set myself.

“These have both been both huge rounds for very different reasons. This was definitely the round that got me back into the championship.”

The Open 2017: Jordan Spieth takes two-shot lead on day two – as it happened Read more

Perhaps the most curious round of the day came from Bubba Watson, who for a spell looked like he had finally come to terms with the vagaries of links golf. Watson sat third at four under par after six holes. He proceeded to make bogey three holes in a row, take a double bogey at the 10th and play the closing eight in one under.

This all added up to 72 and an even par total, with Watson continuing his strange day by attempting to dodge post-round media duties. “I wasn’t reluctant because I wasn’t happy with my round,” explained the 38-year-old. “I just didn’t want to come up here. It’s the same questions every week.”

The man child was back. “I don’t know how you played that hole today but it’s very difficult,” was a subsequent response to a journalist who questioned a wayward tee shot. The world eagerly anticipates the bold Bubba’s 1,000-word live major reports.

There was Friday joy for Alfie Plant, who secured the silver medal for the Open’s leading amateur as the only one to survive for the weekend. Plant’s 73 included a crucial eagle at the 15th. How the 25-year-old is entitled to revel the next 48 hours.

Among those to miss the cut were Phil Mickelson, who has not tasted victory at all since lifting the Claret Jug in 2013. Mickelson’s 77 left him at 10 over par.

“It’s just one of those things where if it starts going bad in these conditions, it’s just going to go bad,” Mickelson said. “It’s not that big a deal. Unfortunately it’s the first cut I’ve missed this year and I missed it with flair. I was surprised because I really thought I was prepared. I felt like I was ready. I thought I had a good gameplan. I thought my game was sharp. But obviously it wasn’t.”

Mickelson was joined by Mark O’Meara, who earlier announced he will not play in another Open. “I’ll miss it,” O’Meara said. “I can tell you that much, I’ll miss it.” Hopefully the 1998 champion at least watches from afar; the 146th joust for the Claret Jug has all the criteria to be one for the ages.