ROME, Italy – Christina McHale celebrated her 24th birthday by scoring another good win over a quality opponent, beating Ana Ivanovic, 6-7(3), 6-4, 6-1 to advance to the Round of 16 at the Internazionali BNL d’Italia. Currently ranked No.56, McHale has quietly put together a strong four months that has seen her notch wins over Garbiñe Muguruza, Karolina Pliskova, Samantha Stosur, and Caroline Garcia.

Once ranked as high as No.24 in 2012, McHale finally seems to have put her injury and illness woes behind her.

“I think I’m physically stronger now,” McHale told WTA Insider. “I worked a lot on my fitness and I think that’s been a key for me, is to get stronger. In terms of my game I think my game is the same. You definitely try to make improvements to your game but the base of my game hasn’t changed. I try to look for forehands and rely on my movement a lot.

“But in the past couple of months in particular I’ve been healthy, which is key for me. I had the mono a few years back and I had a shoulder injury last season. Knock on wood I’ve been healthy. If you can train for matches, anything can happen.”

Her win over Muguruza at the BNP Paribas Open was her first over a Top 10 player since she beating Caroline Wozniacki at the Aegon International in 2012. Later that fall, McHale was diagnosed with mononucleosis and she was unable to back up her results in 2013, falling to as low as No.114 in the rankings. As she fought to get back into the Top 50, a shoulder injury stalled her entire 2014 off-season.

“I had a small SLAP tear,” McHale said. “I felt it on my serve. I didn’t serve once the entire off-season. Then I went to Australia and tried to play through that and it just wasn’t getting any better. After Australia I had to take a whole month off and do a bunch of rehab or therapy on it. “

Given her rise through the rankings four years ago it’s easy to fall into the trap of thinking the New Jersey native is still one of the young guns on the tour. But at 24-years-old, McHale even admits she’s much more wary about the wear and tear on her body these days. Gone were the days she could just walk on court with minimal warm-up and play a three-set match. She’s had to become much more professional in how she treats and protects her body.

“I notice I have to take a lot more care of my body now,” McHale said with a laugh. “I have a whole routine I do for my shoulder, just to keep it good. All the stretching and stuff that I didn’t do in the beginning of my career.”

But her resilience has paid off. Last month she scored a key win for the United States Fed Cup team in sealing a win over Australia, beating Stosur in a tough three sets. Of all the wins she’s racked up this season, this was the sweetest.

“It was just so special to have a win that meant so much for the team and playing Fed Cup is such an honor,” she said. “I think it had been four years since I had a Fed Cup win so it was really exciting for me.”

Next up for McHale is the ultimate test in tennis: Serena Williams. The two Americans will face off for the second time in two months. McHale took Serena to three sets at the Miami Open in April, only to lose 6-3, 5-7, 6-2.

“It was the first time I had played her in a match,” McHale said. “It’s really good that I’ve had that experience, but she’s the type of player that when she’s on there’s really not much you can do. But I’m going to compete really hard and try and impose my game like I did in Miami.”

Asked whether there were rumblings in the locker room about the possibility of some signs of vulnerability from Serena this season, McHale beamed a knowing smile. Come on, you guys. This is Serena.

“In my opinion, you can never count her out,” she said. “She’s done everything she’s done for a reason. You have to be ready. No matter what the circumstances are she’s super tough.”

All photos courtesy of Getty Images.