The Walker Cup has always been a stomach-churning experience for those involved in its absorbing cut-and-thrust but it was more than butterflies doing the rounds as the 48th edition of this grand transatlantic tussle got underway at Seminole in Florida yesterday.

A series of “gastrointestinal issues” prior to the opening session affected 14 players and both the USA and GB&I captains. It led to the travelling reserves being plunged into action as the powers that be allowed flexibility and the use of substitutes.

The tummy bug seemed to move through the squads quicker than a putt on Seminole’s lightning quick greens but, when things settled down, Stuart Wilson’s GB&I team showed they had, well, the stomach for a fight.

By the end of the first day of four foursomes and eight singles ties, it was the hosts who had a forged a 7-5 advantage. With another four foursomes matches and a finale of 10 singles on Sunday, there’s still plenty to play for.

GB&I certainly gave it their all, particularly in the opening exchanges of the morning which could easily have drifted away from them.

In a series of engrossingly nip-and-tuck foursomes encounters which all went to the 18th green – the first time that has happened since 1983 – the honours were eventually shared 2-2.

Given the USA had significant leads in three of the four matches heading onto the back nine, it was an admirable salvage operation from a visiting side seeking just a third Walker Cup win on American soil and a first since 2001.

Wiltshire’s Jake Bolton, who was originally a reserve, rose to the occasion after being sent to the front and helped to bolster the GB&I assault against Stewart Hagestad and William Mouw. Bolton holed a curling 30-footer for a hole-winning par on the 17th, after playing partner Adam Flanagan had dunted a fine recovery shot on to the green, before firing a brilliant approach into 10-feet at the last to all but ensure a one-hole win in the anchor match.

It had been a morning of tightly fought affairs. In the top match, the GB&I duo of Alex Fitzpatrick and Barclay Brown had been three down through 13 against Cole Hammer and Davis Thompson but rallied to square the match at the 16th.

The GB&I pairing lost the 17th, however, and hope of stealing a half were dashed on the last when Hammer dealt the ultimate blow with a raking putt for birdie to seal a narrow win. “It was a wild match,” said Hammer of a joust of fluctuating fortunes.

The Irish partnership of John Murphy and Mark Power, meanwhile, had been three-down after 12 against Quade Cummins and Austin Eckroat but won four of the last five holes to win by one hole and complete a thrilling turnaround.

Despite Jack Dyer and Matty Lamb falling to Mac Meissner and Ricky Castillo, GB&I would have been more than happy with a share of the spoils heading into the afternoon’s singles.

Those head-to-head duels provide plenty of intrigue. In the top match, Fitzpatrick, the world amateur No 12, was floored late on by Pierceson Coody, the grandson of former Masters champion Charles. Coody won the tough 17th with a bogey and then sealed the deal with a birdie on the last for a two hole win.

Power, Lamb and Brown would all put points on the board for GB&I but Flanagan, one up with three to play, succumbed by one hole to Eckroat as the USA prised a crucial lead by taking the session 5-3.

“It’s been a hard fought day,” said Forfar man Wilson. “They still need to sharpen up on things. The 17th, for instance, was playing tough but I didn’t see anyone of our guys hit the green today. We need to tighten up.”

Hopefully the dodgy stomachs hold up too. The final day will require hardy resolve.