Japan's Takashi Sanada gained arguably his biggest career win on Wednesday at the Florida Open, the first Super Series event of the 2011 NEC Wheelchair Tennis tour, after beating eighth seed Frederic Cattaneo (FRA).
In a tense and close encounter, world No. 10 Cattaneo became the first seed to exit this week's tournament in Boca Raton, USA, as Sanada progressed 7:6 5:7 6:3 to earn a second round match against Junior Maters champion Gustavo Fernandez of Argentina. Fernandez but himself in with a change of reaching his first Super Series quarterfinal in all-South American first round match against Brazil's Carlos Santos, Fernandez easing to a 60 63 win.
Meanwhile, former Florida Open champion Michael Jeremiasz (FRA) and one of last year's quarterfinalists, Britain's David Phillipson, were also involved in an enthralling contest, with Phillipson taking a commanding third and deciding set lead. However, former world No. 1 Jeremiasz fought back to eventually prevail 3:6 7:5 7:5.
Elsewhere, there were comfortable wins for all the seeded players, with the pick of Thursday's second round matches including Jeremiasz's head-to-head with Dutch third seed Ronald Vink and his compatriot Frederic Cazeaudumec's meeting with Japanese seventh seed Satoshi Saida.
Meanwhile, after young Dutchman Tom Egberink took this week's world No. 2 Stephane Houdet to three sets for the first time at last week's Pensacola Open, the two players go head-to-head again on Thursday in Boca Raton.
Just six women's singles matches were needed on Wednesday to complete the round of 16, with by far the closest of those between Switzerland's Sue Bertschy and Jan Proctor of the USA, with Proctor holding on 6:3 7:5 to progress along with Germany's Sabine Ellerbrock, Japan's Mino Nijo, Yuka Chokyu of Canada and Chile's Maria Antonieta Ortiz.
The most intriguing of the second round matches sees Ellerbrock take on Dutch world No. 5 Aniek van Koot, just a week after beating world N. 6 Annick Sevenans to reach the Pensacola Open quarterfinals.
Meanwhile, Nijo will be the first opponent for world No. 1 Esther Vergeer, world No. 10 Jordanne Whiley faces a tough opener against South Africa's Kgothatso Montjane and Ortiz will hope to provide a stiff challenge for sixth seed Marjolein Buis.
There were three three set matches on the opening day of quad singles competition, with Japan's Takashi Nagaoka winning 12 of the last 15 games of his match against American Pani Herath as Nagaoka came from a set down to win 4:6 6:0 6:3.
The closest quad singles match of the day saw Britain's John Parfitt also come from behind before eventually edging out Takahiro Koga of Japan 4:6 6:3 7:5.
Meanwhile, Canada's Adrian Dieleman recovered from dropping the second set of his opening match without winning a game, going on to beat Britain's Antony Cotterill 6:3 0:6 6:2.
Parfitt, Nagaoka and Dieleman will progress to second round matches against American third seed Nick Taylor, fourth seed Sarah Hunter of Canada and Swedish fifth seed Anders Hard respectively. while top seed David Wagner faces Israel's Noam Gershony.