Coco Gauff Leaves Serving Troubles Behind with Strong US Open Start Against Zeynep Sonmez

For Coco Gauff, last year's US Open was marked by a particularly difficult problem: her serve. Images of the American practicing her serves alone in the rain became a symbol of just how hard she was working to overcome the weakness in her game.

Twelve months later, the picture looks very different. The 22-year-old American has returned to New York with far greater confidence in one of the most important shots in tennis.

The fourth seed defeated Turkey's Zeynep Sonmez 6-3, 6-4 in the opening round, with her improved serve playing a major role in the victory.

A major problem a year ago

Gauff entered last year's US Open struggling badly with her service motion. Double faults were becoming increasingly costly, while hesitation during service games was putting unnecessary pressure on the two-time Grand Slam champion.

The problem became so significant that Gauff continued practicing even in persistent rain, determined to find a solution before competing on one of the biggest stages of the season.

Following a difficult Cincinnati Open, where she produced a high number of double faults, Gauff made a major change to her coaching team. She brought in biomechanics expert Gavin MacMillan, who had previously helped Aryna Sabalenka overcome her own serving difficulties.

Changing such an important part of her technique immediately before the US Open was a considerable risk. Gauff ultimately struggled in New York and was eliminated in the fourth round.

A completely different Gauff

One year later, Gauff's serve has become a much more reliable weapon. She still produces the occasional double fault, but her consistency and confidence have improved significantly.

MacMillan focused on several technical details, including making Gauff's ball toss more consistent, preventing her from throwing the ball too far forward and keeping her wrist straighter through the motion.

The changes have allowed Gauff to improve her accuracy without sacrificing the speed that makes her serve so dangerous.

Her title run at the Cincinnati Open earlier this month provided one of the clearest signs of that progress. Analysis from the tournament showed that Gauff was serving closer to the line while maintaining impressive pace.

Her opening-round performance against Sonmez offered further evidence of that transformation.

Gauff's serve makes the difference against Sonmez

Gauff immediately established her authority on serve. She opened the match with a 112mph ace down the middle, followed it with an unreturned first serve and another ace, holding in less than 90 seconds.

Sonmez found it particularly difficult to return Gauff's first serves during the opening set. The American won 93% of the points behind her first serve in the set.

The second set was more competitive. Gauff broke early, but Sonmez fought back and reached three break points while attempting to take a 4-2 lead.

This was where Gauff's renewed confidence became particularly visible.

She produced a precise wide ace followed by an unreturned first serve at around 115mph to escape a dangerous service game. A year ago, the same situation might have resulted in Gauff losing the game. This time, she held firm.

She immediately broke Sonmez's serve to move 4-3 ahead before eventually closing out the match.

"I can go for the ace now"

Gauff's biggest improvement may not simply be technical. It is also psychological.

The American now trusts her serve enough to use it aggressively in important moments rather than simply hoping to get the ball into play.

In the final stages against Sonmez, Gauff hit three consecutive unreturned first serves, all approaching the 120mph mark. The sequence helped her earn three match points, and she converted the first opportunity to complete the victory.

Gauff said she now feels comfortable enough to target aces and high-speed serves, explaining that her mindset has changed dramatically compared with last year.

Instead of simply hoping that her serve would land in, she now believes she can consistently reach speeds of 110, 115 or even 120mph when conditions allow.

A valuable experience for Zeynep Sonmez

The defeat ended Zeynep Sonmez's US Open campaign in the first round, but the match nevertheless provided valuable experience for the Turkish player.

Sonmez managed to make the contest highly competitive during the second set against one of the world's leading players. However, Gauff's improved serving ultimately proved to be one of the decisive factors.

The transformation from last year's serving struggles to a weapon she can now trust could prove to be one of the most important developments of Gauff's career.

The American will face either Spain's Paula Badosa or Australia's Daria Kasatkina in the second round. As the tournament progresses, the question will be how far Gauff's renewed confidence behind her serve can take her in New York.