Juan Martin del Potro’s comeback continues to gather steam with the Argentine steadying to close out Bosnian Damir Dzumhur to reach the Delray Beach Open quarter-finals on Thursday night. The 2011 champion, in just his second match of the season, put paid to his 24-year-old opponent’s fight-back to land a 7-6(5), 4-6, 6-3 victory.

“It was a really tough match for me,” del Potro said. “He was really fast from the baseline and I couldn’t find the place to make winners with my forehand.

“I got my chances at the end of the match and I took it. I think I played my best game in the third set.

“He was trying to put the ball all the time to my backhand and coming to net when I sliced. He was smart but in the end I was more offensive from the baseline and came to the net in the important moments and that was the difference.”

Del Potro showed signs of rust in the first set, hitting five double faults, including two in the eighth game when he gave back a break. He lost eight of his first nine second-serve points up to the moment at 4-5 when he was down set point. He toughed out that danger on his second serve and avoided consecutive breaks to level the match at 5-all.

Showing signs of frustration, the seventh seed violently slammed his racquet strings into his head in the following game when he missed a makeable forehand passing shot at deuce. Despite his fifth double fault in the tie-break, del Potro took the first set and soon after broke for 3-1 in the second.

Following three surgeries on his left wrist in 2014 and ’15, del Potro again hit his double-handed backhand conservatively and mixed in slices. His full-throttle forehand was dangerous at times but also often erratic. 

Having handed the break straight back with a wild forehand error, a subsequent double fault on break point at 4-all cost the Argentine a second break of serve and, one game later, the set.

With games on serve in the deciding set, Dzumhur rallied from 0/40 but then double faulted at deuce. The game ended with both men at net, where del Potro reached high for a backhand smash winner to clinch the pivotal break and go ahead 4-2.

Dzumhur was staring down match point on serve at 2-5 but survived when del Potro missed wide off the backhand return. He held to force his opponent to serve it out.

Del Potro brought up match point No. 2 with a crunching forehand crosscourt winner. He closed it out when Dzumhur scrambled back for a lob and missed a tweener attempt.

In a battle of Delray Beach champions, del Potro will next take on defending champion, fourth seed Sam Querrey. The American earlier scored a convincing 6-2 6-3 result over his countryman and doubles partner Jared Donaldson to reach the quarter-finals.

“It’s going to be a completely different match,” del Potro said. “He serves as strong as me and plays really fast from the baseline. He’s the favourite to win because he beat me last time in this tournament and he has the higher ranking than me.”

In doubles, top seeds Bob Bryan and Mike Bryan won an all-American clash to reach the quarter-finals. They downed Jared Donaldson and Sam Querrey 6-4, 7-5 to set a quarter-final match with Yen-Hsun Lu and Leander Paes. Third seeds Treat Huey and Max Mirnyi await the winners. Huey and Mirnyi downed Tommy Haas and Vasek Pospisil 7-6(5), 6-2.

Jonathan Erlich and Scott Lipsky ground out a 2-6, 7-6(5), 11-9 victory in an all-unseeded battle over Brian Baker and Nikola Mektic.

They will face Raven Klaasen and Rajeev Ram for a place in the final. The second seeds snuck through against Purav Raja and Divij Sharan 7-5, 7-5.

Jamie Murray recorded the 300^th match win of his doubles career by partnering Bruno Soares to a 6-3, 5-7, 11-9 quarter-final win at the Rio Open presented by Claro over Andres Molteni/Diego Schwartzman.

Murray/Soares nearly squandered a 9/5 lead in the Match Tie-break, but recovered to prevail on their fifth match point. The top seeds now go on to face either third seeds Pablo Carreno Busta/Pablo Cuevas, who advanced 6-4, 7-5 over qualifiers Facundo Bagnis/Gastao Elias.

Fourth seeds and defending Rio champions Juan Sebastian Cabal/Robert Farah continued their win streak with a 6-2, 6-2 victory over Nicholas Monroe/Artem Sitak. The Colombian Power took the title last week at the Argentina Open.

Fourth seed Pablo Carreno Busta weathered a stern test on Thursday from Victor Estrella Burgos to reach the quarter-finals of the Rio Open with a 6-2, 4-6, 6-2 win.

Carreno Busta comfortably cruised through the opening set but Estrella Burgos, who received a Lucky Loser spot into the main draw after Gerald Melzer withdrew due to illness, grabbed the lone break in the second set at 5-4 to send the match into a decider. But the Spaniard was not to be denied, breaking Estrella Burgos twice and dropping just five points on serve to wrap up the contest in one hour and 42 minutes. He improves his FedEx ATP Head2Head record over the Dominican Republican player to 2-0.

Next up for Carreno Busta is Alexandr Dolgopolov, who extended his win streak to seven matches with a 7-6(4), 4-6, 6-4 victory over Horacio Zeballos. The Ukrainian won his first ATP World Tour title in five years by defeating Kei Nishikori in last week’s Argentina Open final.

The Spaniard will seek revenge on Dolgopolov after losing to him in their lone FedEx ATP Head2Head meeting last week in the Buenos Aires semi-finals.

The top two seeds Gael Monfils and Jo-Wilfried Tsonga pleased the French crowd on Thursday evening at the Open 13 Marseille as they both advanced to the quarter-finals with straight-sets wins.

Monfils needed just 57 minutes to dismiss qualifier Sergiy Stakhovsky 6-1, 6-4. The right-hander dropped just eight points on serve as he set a quarter-final clash with countryman Richard Gasquet. The pair have met 12 times, with Monfils leading their FedEx ATP Head2Head series 7-5.

The 30-year-old Monfils is returning to action this week for the first time since his fourth-round showing at the Australian Open (l. to Nadal). The Frenchman, who qualified for the ATP Finals for the first time last year, is looking to go one better than his run in Marseille in 2015, when he finished runner-up to Gilles Simon.

Second seed Tsonga was a 6-3, 6-3 winner over Illya Marchenko, saving all six break points the Ukrainian created to advance in 81 minutes.

Tsonga goes on to face 2015 champion Simon as he bids to win his second ATP World Tour title in as many weeks. The Frenchman is coming off his first title in 17 months after lifting the trophy in Rotterdam last week (d. Goffin).

The 31-year-old Tsonga is a two-time former champion in Marseille, hoisting the trophy in 2009 (d. Llodra) and 2013 (d. Berdych), while also finishing runner-up in 2014 (l. to Gulbis). 

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Novak Djokovic will delight his Latin American fans by making his ATP World Tour debut in the region next week after accepting a wild card into the Abierto Mexicano Telcel.

The World No. 2 in the Emirates ATP Rankings joins a stellar field that featuring five other players inside the Top 10, including Milos Raonic, Rafael Nadal, Marin Cilic Dominic Thiem and David Goffin. Rounding out the lineup are Juan Martin del Potro, Nick Kyrgios and Ivo Karlovic.

The Serbian’s only tournament in Latin America as a junior or pro was the 2016 Rio Olympics (l. to Del Potro in 1R). He played three exhibition matches in Chile and Argentina during the 2013 off-season, two of which were against Nadal.

Djokovic is competing in his third ATP World Tour event of the season, having opened the year by defeating Andy Murray in the Doha final before receiving a surprise second-round loss at the Australian Open to Denis Istomin. He has not competed since scoring a victory over #NextGenATP Karen Khachanov during Serbia’s 4-0 first-round Davis Cup win earlier this month over Russia.

Fourth seed Sam Querrey moved forward with his title defence on Thursday at the Delray Beach Open, scoring a convincing 6-2, 6-3 win over fellow American and doubles partner Jared Donaldson to reach the quarter-finals.

“I was just swinging freely through everything and did a good job of committing to it,” said Querrey. “Even if I’m missing, I’m trying to keep doing it if it’s the right play. That’s what I’ve been working on a lot the past couple of days.”

Querrey fired 13 aces and didn’t drop serve, breaking his opponent three times to wrap up victory in exactly one hour. He improved his FedEx ATP Head2Head record over Donaldson to 2-0. The American pair will take the court again during the night session for their first-round doubles match against top seeds Bob Bryan/Mike Bryan.

The fourth seed has been in top form this week, dropping eight games combined in his first two matches. Next up for the American is either Juan Martin del Potro or Damir Dzumhur. Querrey defeated del Potro in last year’s Delray Beach semi-finals en route to the title, but the Argentine leads their FedEx ATP Head2Head rivalry 2-1.

“In a way, I’d rather play Dzumhur,” laughed Querrey. “But it’s great to see del Potro back. He’s definitely at a different level now than he was a year ago. I’ll have to elevate my game if I play him again.”

2015 Delray Beach finalist Donald Young continued his top form at this event, defeating #NextGenATP star Taylor Fritz 4-6, 6-3, 6-4 in their second-round clash.

Young’s quarter-final spot quickly turned into a semi-final berth after his next opponent, Steve Darcis, was forced to withdraw. The Belgian advanced earlier in the day 6-3, 7-5 over Nikoloz Basilashvili. 

In their first ever meeting, Young managed to fend off 13/15 break points to defeat World No. 112 Fritz in two hours.

“It’s all a bit of a blur right now. I was just trying to compete, to fight, and I was able to win. I don’t know how,” said Young. “It’s tough playing these young guys, it brings a different pressure. They want to beat you bad, you don’t want to lose to them. I’ve been there before, the older guys didn’t let me in, so I’m trying to hold them off for as long as possible.”