NEW YORK, NY, USA - Maria Sharapova hoisted the US Open trophy back in 2006, and despite a 6-1, 6-1 defeat to 23-time Grand Slam champion Serena Williams, the former World No.1 remains optimistic that she has room to grow after a shoulder injury stunted her season.

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"It's not an easy road," she said on Monday night. "It's never been. But I went through a shoulder procedure about four months ago. To find myself playing at a night match at the US Open with people excited about the matchup, it's a pretty big deal. I'm fortunate to be a part of that."

It's not the first tough draw she has faced at the US Open of late. Playing her first Grand Slam since the 2016 Australian Open, she drew then-World No.2 Simona Halep in the opening round, winning a dramatic three-setter en route to the second week.

"I won that match in a long battle," Sharapova recalled. "Then I played another few physical matches, which ended up costing me later in the tournament.

"It's tough when you don't play much, then you face tougher opponents. You don't get through those, and it's an uphill battle."

Starting the 2019 season with another tough early draw, Sharapova dethroned Australian Open champion Caroline Wozniacki, only to fall in the fourth round to future World No.1 Ashleigh Barty and miss much of the next six months - including Roland Garros - due to a shoulder injury. A forearm issue forced her to retire from the first round of Wimbledon, but the Russian admitted the shoulder remains the most crucial physical issue.

"You can do all the work in the world, but if you can't go out and hit serves, it's pretty tough. That's been my biggest challenge."

"After the long match against Kontaveit, I struggled with my shoulder for a week or so. I was trying to get that back on track. I think I hit like over 200 serves in that match. That was a lot compared to what I did in practice beforehand. I have to be mindful of the schedule. I have to be smart, but I really want to play as much as I can till the end of the year."

- Maria Sharapova

Looking for new solutions, she spent a post-Wimbledon training block at coach Riccardo Piatti's academy, and lost a tense three-setter to Anett Kontaveit at the Rogers Cup, a match that makes Sharapova cautious to plan an overly ambitious Asian Swing schedule.

"After the long match against Kontaveit, I struggled with my shoulder for a week or so. I was trying to get that back on track. I think I hit like over 200 serves in that match. That was a lot compared to what I did in practice beforehand.

"I have to be smart, but I really want to play as much as I can till the end of the year."

Though her US Open has already come to a close, Sharapova shrugged off questions about whether her career will continue, along with others about her motivation to carry on in the face of growing obstacles.

"Bottom line is I believe in my ability. You can write me off. There are many people that can write me off, especially after going down 6-1, 6-1 in the first round of the US Open.

"As long as it's not the person that's inside of you, you'll be okay."