Four-time Grand Slam champion Naomi Osaka’s poor form continued on Tuesday at the Bad Homburg Open as she fell 6-4, 6-4 against American No. 5 seed Emma Navarro.

Navarro will face compatriot Jessica Pegula on Thursday, after the top seed powered past Czech Katerina Siniakova 6-2, 6-3 earlier.

Osaka had won her first match of the grass season in the first round with a victory in straight sets over Olga Danilovic.

The Bad Homburg Open is the final tuneup before Wimbledon. The former No. 1 has yet to advance past the third round at a major since returning to the tour ahead of the 2024 Australian Open.

In other action, second seed Jasmine Paolini overcame a brave fightback from Leylah Fernandez to beat her 7-6 (8), 7-6 (6) in a dramatic round of 16 clash in which Fernandez saved four match points.

Paolini edged her opponent in the opening set in a tiebreak, saving a set point at 5-4 before sealing it 10-8 after a grueling 26-shot rally.

The Italian looked on course for a straight-sets win when she led 5-2 in the second, but Canadian Fernandez saved a match point with an ace and clawed her way back.

Paolini held more match points at 6-5, but Fernandez saved all three to force a tiebreak. Fernandez went up 6-4 in the breaker, but Paolini held firm, saving two set points before clinching victory on her fifth match point.

Despite converting only five of her 17 break points, Paolini secured her first win on grass this season after a 2? hour match.

“It’s very fun to play on grass, but you have to get used to it and you have to have confidence as well in your game, if not it’s really tough,” Paolini said.

“I really like also to go on the net and doing drop volleys and it’s fun but at the same time it’s a bit tricky.”

Fourth seed Iga Swiatek overcame a slow start to defeat Belarusian Victoria Azarenka 6-4, 6-4. After trailing 2-4, Swiatek broke Azarenka back for 4-3 and held to level.

The Polish star broke again for 5-4 and saved two break points in a tense final game before Azarenka sent a forehand wide to concede the set.

The players traded breaks early in the second set before Swiatek pulled away. After breaking for 4-3, the top seed held serve twice more to seal the win in straight sets.