Elena Rybakina to end season as World No.1 as Naomi Osaka crashes out of Pan Pacific Open

The Pan Pacific Open quarter-final lineup has been completed, and it will be headlined by Elena Rybakina. The No.1 seed commenced her campaign in Tokyo with a convincing 6-2, 6-3 victory over fellow countrywoman Yulia Putintseva, but there is a more significant storyline surrounding this victory.

Rybakina will end the year as the World No.1. Her lead is now insurmountable to Aryna Sabalenka in second. It does not matter what occurs at the WTA Finals in a couple of weeks, the Kazakh will be perched on top of the WTA rankings for the foreseeable future as she looks to back up the Ningbo Open title defence with glory in this WTA 500 event.

After winning their first two encounters, Putintseva has not been able to get the better of Rybakina since. The three-time Grand Slam champion was hopeful in continuing this positive form, and off the bat was the one in control.

The first set took just 29 minutes, and Rybakina was the dominant force. A trio of holds was followed by a convincing break of serve with Rybakina leading 4-1. Outintseva closed the gap to two games, but the 27-year-old has no issue in seeing it out against the serve to storm into a resounding lead.

It would soon get better for Rybakina and more daunting for Putintseva. It was most certainly an uphill task after going a set and break down. A hold to love was backed up with a clinical break as Rybakina completed the three-game spurt to lead 4-1.

Putintseva attempted a very late comeback, holding to love as she forced Rybakina to serve it out on her own terms. The first match point was missed as a break point was created but crucially was not taken. Rybakina got the match wrapped up and blasts into the next round. That is now five wins in a row and two matches without being broken. Rybakina is moving up the gears at the right time and will be a force to be reckoned with for the rest of 2026.

There was a huge upset on home soil for Naomi Osaka. The Japanese No.1 was heavily touted for a deep run but exited at the second round stage in stunning fashion against 18-year-old wildcard Mia Pohankova, losing 6-3, 7-5.

On paper, this seemed like this should have been a routine victory for the four-time Grand Slam champion, but tennis is rarely that simple. Osaka looked to have shown a real statement of intent after taking a 2-0 lead, but with a fourth break point, the Slovakian was quickly back on level terms. At 3-3, Pohankova would then storm clear. She won eight of the next nine points before converting a third set point against the serve to take an unexpected lead.

She was one set away from the biggest and most significant win of her career in terms of a ranking and tournament perspective. The second set was a procession of holds. Two break points were created in the opening 11 games, both going in separate games for Osaka but her clinical edge was missing. This would come back to bite her. Pohankova finally made some inroads against the serve, creating a solitary match point. She converted it, and the upset was complete.

It is a first ever WTA quarter-final for last year's junior Wimbledon champion and was done by defeating a former World No.1. For Osaka, that is now three consecutive tournaments where she failed to reach the quarter-finals. That comes after making that stage in the four prior events, meaning that momentum has faded in a painful loss in front of an adoring home crowd.

Pohankova will take on Alycia Parks in the last-eight in what is a golden opportunity for both players. She battered Kimberly Birrell 6-3, 6-1 in a convincing manner, not giving the lucky loser a chance.

Birrell was the first to seize the breakthrough, going 2-1 to the good. However, she would win just two games from that point. Parks made it four games on the spin to lead 5-2 before a brace of holds culminated the opening set. Eight of the first 10 points in the second set went the way of Parks, and another break of serve seemed to be the writing on the wall for the Aussie. Parks won the final four games and is in a first quarter-final since the end of August in Monterrey.

The other last-16 contest was played out between Leylah Fernandez and Elise Mertens. They had endured a thrilling matchup in the early stages of the Ningbo Open, in which the Canadian prevailed in en route to the final. While it did not go the distance, Fernandez was again the triumphant victor on the day, winning 6-2, 7-6(8).

Four holds of serve commenced proceedings. Mertens had the first break point of the match, but it was the former US Open runner-up to battle ahead a game later. This started a four-game burst that would close out the first set.

Fernandez improved her situation with the second set breakthrough not taking long. Her 3-1 lead was soon extinguished as Mertens found some momentum, but it seemed like that was it when Fernandez broke to go 5-3 ahead. However, she failed to serve it out before a match point was blown against the serve. A tiebreak was needed to split these two fierce competitors, and it would be a costly one for Mertens. Two set points to prolong the tie were wasted. In the midst of this, Fernandez also had another match winning opportunity slip out of her grasp, but a third cropped up and this one was successfully converted to prolong her positive form. She will face Rybakina in a rematch of that Ningbo Open final.