Shibata defeated Diaz in the last four of the under-21 women's singles competition at last weekend's Bulgarian Open.

In this week's competition in Olomouc, however, the opposite story unfolded in the senior women's category as Diaz progressed to the round of 32 of the Major Series tournament.  

The start of the match was extremely tense and it was not until deuce that game one was decided, with Diaz narrowly taking the lead.

Shibata massively improved in the next game limiting the Puerto Rican to just a single point.

Diaz overcame the setback and managed to swing the pendulum her way once more.

Back-to-back ends put Diaz 3-1 ahead and the momentum was back in her direction.

Shibata attempted a fightback by taking game five, but Diaz went on to win the sixth and decisive game to complete her revenge 12-10, 1-11, 11-9, 11-2, 8-11, 11-8.

Elsewhere in the women's competition, Germany’s Sabine Winter narrowly avoided a shock defeat to Lin Po-Hsuan of Chinese Tapei, as their match went right to the wire.

Winter, ranked 48th in the world, looked guaranteed to progress after going two games in front against Lin.

Out of nowhere, however, Lin stole three consecutive ends to move to within a game from achieving an almighty upset.

Winter held her nerve, though, to win 11-7, 12-10, 6-11, 8-11, 7-11, 11-6, 11-9 and secure a last 32 encounter with Russia’s Maria Dolgikh.

Winter also made it through to the quarter-finals of the ladies doubles alongside compatriot Kristin Silbereisen.

The German duo beat home favourites and Czech pair Renata Strbikova and Lenka Harabaszova by three games to one.

Elsewhere in the women's doubles Sweden's Matilda Ekholm and her Hungarian partner Georgina Pota beat Romanian duo Irina Ciobanu and Camelia Postoaca 4-0 to progress to the quarter-finals.

In the men's singles the highest seeded player left in the competition, Japan's Mizuki Oikawa, progressed to the last 16 with a 4-2 win over Denmark's Jonathan Groth.

There was also a win for Patrick Franziska of Germany. 

The 50th seed overcame Cedric Nuytinch of Belgium in straight games 4-0.

Yuya Oshima, ranked 30th in the world, also advanced as he beat Alvaro Robles of Spain 4-1

South Korean duo Eonrae Cho and Jeongwoo Park made it through to the quarter finals of the men's doubles tournament as they dominated German pair Kilian Ort and Dang Qiu 3-0. 

There was some German success, however, as Ruwen Filus and Xi Wang, who gained German nationality last year having switched from China, overcame Chinese Taipei duo Liao Cheng-Ting and Sun Chia-Hung 3-0.