Maria Sharapova will take the court Friday night at the U.S. Open in New York, the latest step in a return to the court for the five-time Grand Slam champion following a 15-month ban by the International Tennis Federation (ITF) for taking the banned substance meldonium.

Sitting in the Russian tennis star’s personal box will be Fox Rothschild litigation co-chair John Haggerty, who was also in attendance on Monday when Sharapova beat No. 2 ranked Simona Halep in her first official match in 19 months.

Haggerty, based near Philadelphia, worked with fellow Fox Rothschild litigation partner James Clark and associate Stephan Cornell in representing Sharapova in her year-long fight against doping allegations.

“To be able to sit there and watch her return to the biggest stage in tennis and perform at such a high level, it’s such a great feeling,” Haggerty said. “I’ve got all my fingers and toes crossed that she continues to win and it would be wonderful to see her make it all the way to the finals.”

In January 2016, Sharapova failed a drug test at the Australian Open. She announced two months later that she had tested positive for meldonium, a drug marketed as mildronate that had been made illegal by the World Anti-Doping Agency the same month that she tested positive for the substance, which is not approved for sale in the United States.

“They take doping violations very serious,” Haggerty said of the ITF, “[but] the punishment doesn’t always fit the crime when it’s something inadvertent like happened with [Sharapova].”

Meldonium is manufactured by Latvian drugmaker AS Grindeks to treat heart and circulatory conditions, but was barred because it also increases endurance and oxygen intake. Sharapova said—and Haggerty asserts—that she had been prescribed the drug mildronate by her physician and had been taking it for over a decade because of a magnesium deficiency, irregular electrocardiograms and a family history of diabetes.

In June 2016, the ITF, a London-based global governing body for tennis, initially handed Sharapova a two-year suspension for the violation. But the ITF’s decision was reduced to a 15-month ban in October of that year by the Court for Arbitration for Sport (CAS), a Switzerland-based body that adjudicates international sports disputes.

“[The ITF’s] goal is to show that their sport is drug-free and if there’s ever a violation they’re going to be very heavy-handed in punishing it,” Haggerty said. “[They want to] send a message not just to all the athletes, [but] to the world, to say that we really enforce and police drugs in our sport.”

While acknowledging that noble pursuit, Haggerty said that strict punishments like Sharapova’s can have life-changing consequences for athletes whose careers can often last only a decade or less.

“If you’re going to hold the athlete to such a high standard and have such a high penalty, then you better make sure you’re doing everything you can within your power to provide notice and publication of changes to your prohibitive list [of substances],” said Haggerty, adding that by doing so athletes will be better informed about staying on the right side of new protocols.

Haggerty (pictured right) first began representing Sharapova more than a decade ago following a successful relationship with her talent agency, IMG Worldwide, now called William Morris Endeavor Entertainment LLC after a $2 billion deal in late 2013. Haggerty, who joined Fox Rothschild in 2009 from Ulmer & Berne, also now serves as co-chair of the firm’s class actions group and focuses his practice on complex commercial, insurance and products liability matters.

In his working advising professional athletes, Haggerty advises on any number of legal matters that they may face, from contract disputes to sponsorship deals. Following his handling of Sharapova’s case, Haggerty said that several other international athletes—he declined to name them, citing client confidentiality—have reached out to him for assistance on doping-related charges. He sees positive strides in the dissemination of information by the ITF—Haggerty is unrelated to the organization’s current president, David Haggerty—on prohibited substances

“I think if there’s a silver lining in the awful experience that [Sharapova] had to go through it’s that the governing bodies are now doing an improved job of providing notice to athletes when a substance is added to the prohibitive list,” Haggerty said. “[Hopefully going forward] we can avoid an unfortunate circumstance like this, where an athlete unknowingly is taking a substance which was once legal, becomes prohibited and they didn’t know about it.”