Wimbledon 2014: Roger Federer and Rafael Nadal go through

Nadal next faces Lukas Rosol, who knocked him out in 2012

Seven-time champion Roger Federer eased into the second round at Wimbledon after beating Italian Paolo Lorenzi in straight sets.

The Swiss fourth seed was barely troubled in a 6-1 6-1 6-3 win over a player who has never won a match at a Grand Slam in 13 attempts.

World number one Rafael Nadal was forced to work harder to beat dangerous Slovak Martin Klizan 4-6 6-3 6-3 6-3.

The Spaniard will face Lukas Rosol, who upset him in 2012, in the second round.

Federer, who finished his match with an ace and will next face either Gilles Muller of Luxembourg or Frenchman Julian Benneteau, was happy with his opening effort.

"Getting the first one out of the way is always a good feeling," said the 32-year-old. "I thought I played well, got a lot of breaks and served well.

"Walking down the tunnel I felt relaxed and happy to go on court but once you step out there you are ready and you do feel some pressure."

Lorenzi's record is the second worst in men's Grand Slam history with only Juan-Antonio Marin of Costa Rica (no wins, 17 losses) below him but Federer paid tribute to the 32-year-old world number 83.

"I didn't know about his record beforehand," he said. "I thought he did a good job by trying to serve and volley and make the plays but he maybe doesn't have a strong enough serve to do that."

The win for Nadal, who was beaten in the first round last year by Belgium's Steve Darcis, was his 700th top-level career victory.

"It means I have had a very long and successful career and I am so happy for that, but the most important thing today was the win," he told BBC Sport.

"I really know it is impossible to play my best in the first round. For sure the next round will be tough. The last three years I did not play much on grass and that affects your rhythm and confidence.

"Lukas Rosol is a very dangerous player - very strong and powerful. I will have to play very well if I am to win."

Federer's compatriot Stan Wawrinka has a poor record on grass, losing in the first round in three of the last four years at SW19.

But the Australian Open champion, seeded fifth, served solidly to come through 6-3 6-4 6-3 against world number 41 Joao Sousa of Portugal.

Elsewhere, the eighth seed Milos Raonic from Canada, 10th seed Kei Nishikori of Japan and 14th seed Jo-Wilfried Tsonga also advanced to the second round.

2002 champion Lleyton Hewitt had a gutsy win after first-round exits at the Australian and French Opens

Raonic defeated Australia's Matthew Ebden 6-2 6-4 6-4 while Nishikori beat France's Kenny De Schepper 6-4 7-6 (7-5) 7-5 and Tsonga went through after completing a five-set win over Austrian Jurgen Melzer.

The Frenchman had led his Austrian opponent 5-4 in the decider when play was suspended on Monday evening.

When play resumed Tsonga needed just four points on his own serve, sealing victory with his 20th ace to wrap up a 6-1 3-6 3-6 6-2 6-4 success.

"It is hard to come back to play only one game because you expect a day of rest and then you have to practise," Tsonga, who will play American Sam Querrey in round two, told BBC Sport.

"So it is not easy but it is important to be really concentrated and focused as soon as you are back on the court."

The 2002 champion Lleyton Hewitt, playing in his 16th Wimbledon at the age of 33 and cheered on by a noisy band of Australian fans on court three, went through to the second round after battling to a 6-2 6-7 (14-16) 6-1 6-4 win over Poland's Michal Przysiezny.

But Ivo Karlovic, who beat Hewitt, then the defending champion, in the first round on his Wimbledon debut in 2003, was a surprise first-round casualty. The big-serving 6ft 11in giant, seeded 29, lost 6-4 7-6 (7-5) 7-6 (7-4) to Canadian Frank Dancevic.

Roger Federer, who eased past Paolo Lorenzi, is looking to add to his 17 career Gram Slam titles

Tenth seed Kei Nishikori has never been further than the third round at Wimbledon