This year, as we celebrate the 50th anniversary of the US Open, we’re counting down the 50 most memorable moments in the history of America’s Grand Slam. Today, we take a look back at No. 7.

It was in 1979 at Flushing Meadows that John McEnroe got on the victory board at the majors. In the final, at the age of 19, poised and sharply focused, McEnroe defeated fellow New Yorker and close friend Vitas Gerulaitis in the final.

Returning to the US Open as the defending champion in 1980, McEnroe had been on the edge of an epic triumph in the Wimbledon final earlier in the summer before losing a blockbuster to Bjorn Borg, falling 8-6 in the fifth set, saving seven match points in the fourth set and pulling out a dramatic 18-16 win in a tiebreak.

And so McEnroe arrived at the Open determined to hold onto his title. He confronted Jimmy Connors in the semifinals. He was flowing freely at the outset, winning the first set, reaching set point in the second. But Connors burst into a brilliant stretch from the backcourt, collecting no less than 11 games in a row to lead two sets to one and 2-0 in the fourth set.

play video 50 Moments That Mattered: McEnroe tops Borg in thriller

McEnroe refused to surrender. He came back to win the fourth set. Serving for the match at 5-4 in the fifth set, McEnroe was stung severely by a barrage of big returns from his fellow American. They proceeded to a tiebreak, and McEnroe would not be denied. He triumphed, 6-4, 5-7, 0-6, 6-3, 7-6 (3), in a bruising four-hour, 17-minute battle of left-handers. They battled well into the evening.

Many knowledgeable critics believed a fresher Bjorn Borg was poised to win the US Open the next day for the first time. Twice he served for the first set against McEnroe, but he could not close it out. McEnroe succeeded grittily in a tiebreak, and Borg seemed to temporarily lose heart, dropping the second set swiftly and tamely, 6-1. But the implacable Swede found his range on his returns and threaded the needle on some exquisite passing shots. He made it all the way back to a fifth set.

That final set was locked at 3-3 before McEnroe pulled away to win, 7-6 (4), 6-1, 6-7 (5), 5-7, 6-4, in four hours, 13 minutes. No one in the men’s game since tennis went Open in 1968 had defended a US Open title. McEnroe had beaten Ivan Lendl in four sets on Thursday afternoon in the quarterfinals before eclipsing Connors and McEnroe back-to-back over the weekend. In many ways, it was his finest hour as a professional tennis player.

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