Juan Martin del Potro and Milos Raonic moved into the Delray Beach Open second round with straight-sets wins on Tuesday.
Del Potro, the 2011 champion and second seed in Florida, eased past Jeremy Chardy 6-2 6-4 at the ATP 250 event.
The 2009 US Open winner dropped serve once, but he managed to break his French opponent four times.
Raonic, who underwent wrist surgery in 2017, claimed his first ATP World Tour win of the year, the Canadian ninth seed beating Taro Daniel 6-1 7-5.
Last year's runner-up at Delray Beach, Raonic will next face Steve Johnson after the American beat Nikoloz Basilashvili 6-3 6-4.
Of the four seeds in action, three advanced as John Isner joined Del Potro and Raonic in the second round, serving 21 aces in a 5-7 6-3 6-4 victory over Radu Albot.
Next up for Isner is Peter Gojowczyk, who claimed a 3-6 7-5 6-1 win over Lukas Lacko.
Sam Querrey – the fourth seed and a finalist at the New York Open – fell, edged by Taylor Fritz 2-6 6-3 7-6 (7-4).
@Taylor_Fritz97 upsets No.4 seed Sam Querrey to become the 8th player in the second round, joining @JohnIsner, @ReillyOpelka, @SJohnson_89, @JaredD, @JackSock, @Yimlife1313 & @FTiafoe.— Delray Beach Open (@DelrayBeachOpen) February 21, 2018
: Andrew Patron/#DBO2018 pic.twitter.com/WxB9emesGN
Awaiting Fritz in the second round is Mikhail Youzhny, who won a battle of veterans against Dudi Sela 7-5 6-4.
Canadian teenager Denis Shapovalov beat Ivo Karlovic 7-5 7-6 (7-4) and Franko Skugor was too good for Alexander Bublik 6-2 7-5 in a clash between two qualifiers.
Reilly Opelka sent down 15 aces in a 7-6 (7-5) 7-6 (8-6) win over Ryan Harrison, Evgeny Donskoy brushed past lucky loser Darian King 6-4 6-2 and Jared Donaldson got past Peter Polansky 7-6 (8-6) 6-1.
22 de marzo 2018
|Cavs tally worst defensive half of season against Raptors|
|McIlroy, Johnson stunned on day one in Austin|
|Cristiano Ronaldo hasn´t asked to leave Real Madrid amid China links – Perez|
|Oakland Athletics allowing fans to pick price of tickets, all proceeds to charity|
|Ginobili: Spurs not expecting Kawhi Leonard to return this season|
|Trout, Angels brass confident Shohei Ohtani will be a star|
|Osaka wanted to impress Serena with stunning Miami Open win|
|Manchester United apply for professional women´s team|
|Bolt hopes fellow Jamaican breaks his world record|
21 de marzo 2018
|Bolt a fan of Ronaldo, but compares his talent to Messi´s|
|Outstanding Osaka knocks out Williams in Miami opener|
|Del Potro ´tired´ heading into Miami Open|
|Heynckes definitely leaving at end of season, claims Ze Roberto|
|Joshua tells Wilder to be ´realistic´ in negotiations|
|Shaw issue a distraction from Manchester United´s failures, says Neville|
|Hamsik withdraws from Slovakia squad|
|RFU backs Jones despite awful Six Nations|
|Hamilton eyes Melbourne pole record, 100 club for Vettel? - Australian GP in numbers|
|Griezmann backs Pogba to prove doubters wrong for France|
|Sanchez ´expected something better´ from Manchester United move|
|WATCH: Thomas conjures up great escape in Austin|
|Javi Martinez in the dark over Spain squad omission|
|Jones should have managed England workload - Flood|
|Giggs feeling the tension ahead of Wales debut|
|Juventus confirm Alex Sandro thigh injury|
|Hart praises ´loyal guy´ Southgate amid World Cup axe fears|
|Windies singing in the rain as they clinch World Cup spot|
|I miss Morata, says recalled Costa|
|I can improve even more at Manchester City - Bernardo Silva|
|Neymar will be fit for the World Cup, insists Ronaldo|
|Costa thinks Griezmann will stay at Atletico Madrid|
|Third DRS zone added for Australian Grand Prix|
|Ferdinand worried by England´s World Cup striker options|
|Hamilton an F1 great - Fittipaldi|
|Stam leaves Reading after wretched run|
|Neymar is great, we´ll see if he joins Real Madrid – Asensio|
|Appalling racism must stop - Inglis|
|Maguire tips ´nightmare´ Vardy to replace injured Kane|
|Red Bull duo: Mercedes still the team to beat|
|Wait and see - Root refuses to confirm new-ball role for Broad|
|Malcom ready to leave Bordeaux and chase Bayern ´dream´|
|Surprised Smith says Rabada appeal verdict draws ´line in the sand´|
|Asensio insists Zidane was not unfair to him|
|Griezmann wants future resolved before World Cup|
|F1 2018: Hamilton v Vettel - the race for five titles|
|Nocerino wants Conte return after Italy´s World Cup ´disaster´|
|Celtics capitalise on Thunder meltdown, Harden scores 42 points|
|Jason Day hungry to reclaim top ranking: My game is close|
|Iconic 2002 World Cup haircut was media distraction, reveals Ronaldo|
|New Zealand star Taylor fit for day-night Test|
|Teenager Anisimova to face Muguruza in Miami|
|McIlroy credits Wayne Rooney for improved putting|
|Stokes return a ´huge boost´ for England – Root|
|Wright: Difficult for Liverpool sensation Salah to resist Real Madrid|
|Yaya Toure yet to report for international duty, confirm Ivory Coast|
|Masters favouritism could hinder Woods, Thomas claims|
|I wish I could still play with him – Ortiz on Red Sox addition Martinez|
|Morrison confirms plans to play for Jamaica|
20 de marzo 2018
|Warriors target Friday return for Curry against Hawks|
|Starc and Marsh set to play at Newlands|
|Red alert: Richard Sherman ´excited´ to be a 49er|
|Germany should be proud to have Sane, says Tah|
|Bertrand out of England friendlies with back injury|
|Optimistic McIlroy ´crossed that line´ with Bay Hill win|
|Young backs Mourinho over Shaw treatment|
|BVBolt? Athletics great scores header while training in Dortmund kit|
|Fekir will look to leave Lyon the right way, says agent|
|Ex-Springboks coach Meyer takes charge at Stade|
|Spieth relishing Reed match play showdown|
|Alisson loves Roma and we haven´t discussed Liverpool move, insists agent|