Stan Wawrinka braced for second-round battle against Juan Martin del Potro

The Swiss was a four-set winner over Fritz and will now meet Juan Martin del Potro, the supremely talented Argentinian who - were it not for a series of horror injuries - could well have added to the US Open he won in 2009.

Del Potro has not been seen at Wimbledon since 2013 and was a popular three-set winner over Stephane Robert, prevailing 6-1 7-5 6-0.

He is ranked 165th in the world but clearly has the game to trouble almost anyone and, as a result, Wawrinka is wary of him.

"For me it's going to be interesting to play against him. It's been many years that I didn't play against him. Didn't practice neither," he said after his 7-6 (7/4) 1-6 7-6 (7/2) 6-4 success.

"For sure I think we are all happy that he's back on the tour, hopefully without any injury, and hope that he can play for long now.

"He (has) always been a great champion, a great player to watch also. It's going to be a tough match.

"He has a big serve, big forehand. When you see how tall he is, it's tough to push him, so powerful."

Dustin Brown thrilled Wimbledon's fans once again and is now looking forward to putting on a show against good friend Nick Kyrgios.

The two men - both natural entertainers on the court - grew close at the International Premier Tennis League when they played for the Singapore Slammers.

They are due to be reunited in round two on Thursday, albeit on different sides of the net, after Brown saw off Dusan Lajovic in five sets and Kyrgios beat Radek Stepanek.

"W e played IPTL together, he's a really nice guy," Brown said.

"We are friends. We will go out and have fun and play good tennis. Besides that, I won't worry too much about it."

The dreadlocked German won Wimbledon hearts in 2015 when he unseated the great Rafael Nadal, with his story of how he had travelled around European tournaments in a camper van earning him column inches and plenty of support.

Previously he beat Kyrgios' compatriot, Lleyton Hewitt, in 2013 and is no stranger to causing an upset.

Brown is back in SW19 on a wildcard - he is still ranked just 85th in the world - but looked to be going home as he went two sets to one down against Lajovic.

However, the man nicknamed 'Dreddy' delighted the Court 16 crowd by mounting a fine comeback and took the match 4-6 6-3 3-6 6-3 6-4 to book a second-round spot.

"I concentrate and try and give my best, try to not worry too much about my opponents," Brown added.

Joining Brown and Kygrios in the next phase is Jo-Wilfried Tsonga.

The Frenchman, twice a Wimbledon semi-finalist, beat Spain's Inigo Cervantes 6-4 7-6 (7/5) 6-4 on Court 12.

The 22nd seed, Feliciano Lopez, beat Rajeev Ram in straight sets, Benjamin Becker dropped just seven games to Facundo Bagnis and the 31st seed, Joao Sousa, came through a gruelling clash with Dmitry Tursunov 3-6 7-6 (7/2) 4-6 6-3 7-5.

Other winners on day two included Richard Gasquet, over Brit Aljaz Bedene, along with Viktor Troicki, Yen-Hsun Lu, Juan Monaco and Marcel Granollers.

There was little to concern British number one Andy Murray as he kicked off his run at the title against Englishman Liam Broady.

Murray was too good for the 22-year-old in every department and won 6-2 6-3 6-4.

"I served pretty well. Offensively I thought I did some good stuff. Maybe defensively I could have done a little bit better," Murray said.

"But the first match is always tricky. Obviously Liam... we've never played each before although we've practised a lot and it's not that easy playing someone you know so well, but I did okay."

Albert Ramos-Vinolas snuffed out Vasek Pospisil in four sets and the 14th seed, the improving Roberto Bautista Agut, beat Jordan Thompson 6-3 6-3 6-3.

Gilles Muller and Santiago Giraldo ended their marathon match from Monday, the former taking the decider 15-13 and serving 51 aces.

The rain started to fall just after 4.30pm and play never restarted, leaving the likes of Bernard Tomic and Fernando Verdasco (tied at 2-2), and Tomas Berdych (2-1 up on Ivan Dodig) with uncompleted matches. The eighth seed, Dominic Thiem, was three games into his match with Florian Meyer when the heavens opened.