PARIS, France - Former champion Garbiñe Muguruza survived a first-round test at the French Open.

The No.19 seed christened the brand-new Court Simonne Mathieu with a 5-7, 6-2, 6-2 comeback victory over American Taylor Townsend on Sunday.

Related: Court Simonne Mathieu unveiled ahead of 2019 French Open

The former World No.1 and 2016 French Open champion was befuddled by the left-handed American's variety and pristine drop shots for much of the first hour of the match, but ultimately worked her way into the opening-round affair to seal victory in a minute short of two hours. 

"I knew it was going to be a challenge no matter who my opponent was. We always know that the first rounds are difficult. It's the first match of a Grand Slam, it's a little adventure," Muguruza said after the match.

"Also playing Taylor, she had a different style of game, a very lefty player. She's super talented, so it took me a while to feel better in the court, to get the rhythm to have a game plan. It was a tough match. I'm happy to go through."

Muguruza was broken twice in the first set by the World No.96, hitting just 10 winners to 15 unforced. Townsend, conversely, doubled her winner total (13) in comparison to her unforced errors (6), and proved unfazed after Muguruza leveled the set from a 4-2 deficit. 

"I think I wasn't having the right game plan in the first set. Also, I was trying to play for the first time a new player. We have never faced each other," Muguruza said.

"I think she managed to get the first set, and immediately I realized that, 'Okay, I've got to do something different to turn things around.' A little bit going more forward, playing longer points...I started to feel better in the court and getting my rhythm."

Seeking her second Top 20 victory on clay this season, after beating Julia Goerges at the Volvo Car Open in Charleston, Townsend moved into the lead with an emphatic break to love in the set's final game, and was a point away from building a 7-5, 2-0 lead early in the second. 

The Spaniard saved the break point, however - the lone chance that Townsend had in the second set to break - and took a lead she would not relinquish with a break in the next game.

In a near mirror of the second set, Muguruza was again forced to save just one break point in the third set after Townsend held to open, but a run of 10 straight points helped strengthen the former World No.1's pursuit of victory in the decider.  

"It's a great match, great win. The first matches aren't easy," added Muguruza. "It's only one match at the end of the day also. There are many more matches to go, but for sure it's a great relief to be in the second round."

Townsend ultimately saved three match points to hang on to the eighth game from 0-40 down, but a 40-0 lead on serve by the Spaniard in the ensuing game proved too big of a deficit for the American to again overcome. 

Muguruza ended the match with 33 winners and 28 unforced errors on her statline, which included a margin of 23 winners to 13 unforced over the course of the second and third sets.