Why the US Open Never Had Its Own Isner-Mahut Marathon
Wimbledon let a 2010 final set run to 70-68 over three days before it ever considered a tiebreak. The US Open avoided that fate by adopting one back in 1970.
6-3, 3-6, 6-7(7), 7-6(3), 70-68. Read that scoreline once, slowly, and it still does not look real. John Isner beat Nicolas Mahut in the first round at Wimbledon in 2010 across three days and 11 hours, 5 minutes — a match that could only have happened at Wimbledon, because Wimbledon was the only major left willing to let a final set run forever.
Sixteen years later, none of the four Grand Slams work that way anymore. But for most of tennis history, each one had its own answer to a simple question: what happens when a deciding set reaches six games all? The US Open, oddly, is the one major that never really had a problem to solve.
Why didn't the US Open ever produce its own marathon?
Because it built in a circuit breaker decades before anyone else. Tennis's tiebreak was invented by Newport Casino president Jimmy Van Alen, who came up with the idea in 1954 after watching restless fans wait through an 83-game, five-set final. There had to be a better, more exciting way to control the length of matches without those damnable deuce sets
, Van Alen said, according to the US Open's own account of the rule's history. His nine-point sudden-death tiebreak made its Grand Slam debut at the 1970 US Open, adopted partly because television demanded matches with a predictable end time. Tournament director Bill Talbert defended the change bluntly: We consider this to be a major step forward for the game of tennis. It provides tennis with a finish line, such as we have in racing, basketball, football and other major sports.
In 1975 the US Open swapped the nine-point version for the steadier 12-point, win-by-two tiebreak — and from that point on, no US Open final set could spiral indefinitely, the way Wimbledon's still could.
How big was the Isner-Mahut match, really?
Big enough that Wimbledon's own scoreboard on Court 18 was not built for it. Designed to display scores only up to 47-47, it had to be repaired mid-match once the fifth set blew past its limit, according to Tennis.com's account of the match. The fifth set alone lasted 8 hours, 11 minutes and ran 138 games. Isner and Mahut combined for 215 aces — 112 for Isner, 103 for Mahut — and Mahut served to stay in the match 63 separate times before Isner finally closed it out on his fourth match point. Nothing like this will ever happen again, ever
, Isner said afterward. He was nearly right: it took a second ordeal of his own, an equally absurd 26-24 fifth-set loss to Kevin Anderson in the 2018 semifinals, to finally move Wimbledon off a 133-year-old format.
Why did all four majors finally agree on the same rule?
Consistency, not any single marathon. Wimbledon's first fix, introduced in 2019, was a 7-point tiebreak triggered only at 12 games all — still enough room for a set to reach 24-22 first. The Australian Open moved further and faster, adopting a 10-point breaker at 6-6 that same year. The French Open held out completely, running deciding sets to their natural conclusion until 2022, the last major to blink. That March, all four tournaments jointly announced they would align:
"The Grand Slam Board's decision is based on a strong desire to create greater consistency in the rules of the game at the Grand Slams, and thus enhance the experience for the players and fans alike."
Grand Slam Board joint statement, 16 March 2022, via the Australian Open
The board members who signed it — Jayne Hrdlicka for the Australian Open, Gilles Moretton for Roland-Garros, Ian Hewitt for Wimbledon and Mike McNulty for the US Open — settled on the same math the US Open had used in some form since 1970: race to a target score, win by two, and stop leaving a set's length to chance. Roland-Garros hosted the new unified rule's debut a few months later.
Does any of this change how the 2026 US Open plays out?
Barely, since the tournament already worked this way. This year's edition has produced its own tiebreak drama regardless — the kind of upset streak that ran through this season's majors, on the heels of a Wimbledon fortnight where five-set survival acts were the rule rather than the exception. What has genuinely changed is everywhere else: a classic at Wimbledon or Roland-Garros can no longer spiral into a second sunrise. The number 70-68 is safe for good, preserved as the one scoreline unified rules cannot retroactively erase.
