Heather Watson's second-round hoodoo at French Open continues after defeat by Elise Mertens

The 26-year-old Briton lost in the last 64 for the sixth time in the last eight years when she was beaten 6-3, 6-4 by the world No 16

Heather Watson fell away in the final two games of the match (Getty)

Heather Watson has failed to win a match in only one of her seven appearances in the main draw at the French Open, but progressing beyond the second round is still proving beyond her. The 26-year-old Briton lost in the last 64 for the sixth time in the last eight years when she was beaten 6-3, 6-4 by the world No 16, Belgium’s Elise Mertens.

It was a match of variable quality and frequently fluctuating fortunes. Both women struggled in the early stages in particular and although Watson enjoyed a good spell midway through the second set the world No 80 fell away in the last two games.

Watson made 37 unforced errors to 22-year-old Mertens’ 22, but it was the Briton’s serve that was her biggest problem. She was broken eight times in the match and held serve for the first time midway through the second set.

Earlier this year Watson lost eight tour matches in a row – beginning with her defeat to Mertens in Hobart in January – but her form has picked up in recent weeks. She ended her losing run in Nuremberg last week and then beat France’s Oceane Dodin in the first round here.

Mertens, who had won both her previous meetings with Watson, is based at Kim Clijsters’ academy in the Belgian city of Bree. The former world No 1 has been a mentor for her fellow countrywoman, who has already won three titles this year, including two during the clay-court season.

Her progress up the world rankings has been spectacular. Having begun last year ranked No 124 in the world, Mertens broke into the top 100 for the first time by winning her first title in Hobart in January 2017.

By the end of last year she had climbed into the world’s top 40 and she broke into the top 20 in January with her best run at a Grand Slam tournament when she reached the semi-finals at the Australian Open before losing to Caroline Wozniacki, the eventual champion.

Watson’s second-round hoodoo at the French Open continues (Getty)

Court 3, which was where Watson won her opening match, was almost full for the 11am start. The sun was shining, the temperature a pleasant 21C and only a light breeze blowing, but the high humidity made for a sticky atmosphere. Although there were plenty of British fans in the crowd, a large contingent of Belgian supporters had begun their chants of “Elise! Elise!” even before the start.

The Belgians soon had plenty to cheer as Mertens won 16 of the first 20 points. Watson had a game point for 1-0 but failed to take it and Mertens went on to break with a backhand return winner down the line. Mertens went 3-0 up, but Watson held firm in a lengthy fourth game and broke back when the Belgian double-faulted.

It was a first set littered with mistakes by both women. Mertens looked edgy and struggled to hit the ball consistently, while Watson’s forehand in particular misfired badly.

Mertens eventually proved too much for the Briton (Getty)

Only one of the nine games of the opening set went with serve, when Mertens held for 2-0, and there were 29 unforced errors between the two women and just 12 winners. When Watson served to stay in the set at 3-5 she was broken to love.

A sequence of seven consecutive breaks of serve ended when Mertens held in the opening game of the second set, but the pattern quickly resumed. Watson, nevertheless, finally held serve at the eighth attempt, broke Mertens to love in the following game and then held once more to level at 4-4.

Both players had raised their games significantly by this stage and Watson in particular was striking the ball much more consistently. Mertens, however, held serve for 5-4 and in the following game Watson’s level dipped again. A netted forehand took Mertens to match point, which the Belgian converted immediately when she put another forehand in the net.

“It was very up and down for me,” Watson said afterwards. “I had glimpses of playing well, but I just wasn't consistent throughout the match. And when it was important at 4-4, I just made a few too many errors. And just today, I didn't serve as well as I have been.”

Watson is planning a busy grass-court season, which she will begin in Surbiton next week, unless she goes deep in the doubles competition here with her German partner, Tatjana Maria.

“I'm definitely feeling a lot more positive than I was a couple of weeks ago,” Watson said. “I'm feeling positive and confident and I love playing on the grass.”