His family may have expanded but it was business as usual for Roger Federer as he led the first-round winners on the opening day of play at the French Open.

It is less than three weeks since Federer went from a father of two to a father of four as wife Mirka gave birth to a second set of twins, Leo and Lenny.

All the family have travelled with him to Paris and his four-year-old daughters, Charlene and Myla, were in his box on Court Philippe Chatrier for the start of his 6-2 6-4 6-2 win against Slovakian Lukas Lacko.

Federer lost his first match since the birth of his sons in Rome to Frenchman Jeremy Chardy but was never troubled on Sunday, perhaps not surprisingly given Lacko has not won a match on clay for three years.

He had not even contested a match on the surface since Roland Garros last year and was forced to fight hard for the games he did win.

Lacko saved six of the 11 break points he faced but did not create a single one on the Federer serve, winning just nine points on the fourth seed’s serve in the one hour and 24-minute match.

As could be expected, Federer, who extends his record by playing in a 58th consecutive Grand Slam tournament, was in a very positive mood after the match.

The Swiss said: “Everything is great.

“I’m happy I got off to a good start for the tournament here in Paris. There’s always that little bit of a feeling that if you don’t feel well, if the opponent plays great, whatever happens, you could lose early.

“So I was happy getting early signs out of the match that I was actually playing well and I was going to get my chances I was looking for. I’m very pleased with the outcome of the match.

“My personal life, as we know, it’s all great, so I’m happy the family is here.”

Home hope Jo-Wilfried Tsonga, who defeated Federer in the quarter-finals last year, opened his campaign with a 7-6 (7/4) 7-5 6-1 victory over countryman Edouard Roger-Vasselin.

Sixth seed Tomas Berdych made smooth progress through to the second round with a 6-3 6-4 6-4 win over Peter Polansky of Canada.

One of the most intriguing first-round match-ups pitted eighth seed Milos Raonic against 19-year-old Australian wild card Nick Kyrgios.

The teenager looks set to have a bright future but he found Raonic too tough, the Canadian winning 6-3 7-6 (7/1) 6-3.

Twenty-second seed Jerzy Janowicz broke a nine-match losing streak stretching back to February with a 6-1 6-4 6-7 (6/8) 6-4 victory over Victor Estrella Burgos.

Estrella Burgos, a 33-year-old from the Dominican Republic, was making his first appearance in the main draw of a Grand Slam.

Tenth seed John Isner prevailed in three tight sets against Pierre-Hugues Herbert and could play fellow marathon man Nicolas Mahut in round two.

Mikhail Youzhny and Radek Stepanek both recovered from two sets down and will face each other in the second round.

Defending champion Serena Williams overcame her nerves to defeat friend Alize Lim and stay on course for a third-round meeting with sister Venus at the French Open.

While the 6-2 6-1 scoreline looked like a walk in the park for Serena, her 36 unforced errors showed she was not at her best.

The American needed five match points to get over the line after an hour and 18 minutes and knew she had been in a battle.

Serena said: “A lot of the games went to 30-30 or so. So I think the games were actually pretty close.

“It was interesting. I was a little nervous, like I always am in my first round. It’s always hard for me to shake those nerves and go from there.”

Having been upset in the first round by Virginie Razzano in 2012, Williams won the title at Roland Garros 12 months ago for the first time in 11 years.

She has been arguably more dominant on clay than on any other surface over the past three seasons and came into the tournament on the back of another title in Rome.

“I was in really top form last year on the clay, or at least I thought I was,” said Serena.

“This year I’m just going day by day. I do have to say this year I don’t feel as much pressure on myself as I did last year.”

Lim knows Serena from Patrick Mouratoglou’s academy and could not believe the pair were drawn together a day after posing for pictures at the players’ party at the Eiffel Tower.

She admitted she had thought about the possibility of losing 6-0 6-0 in her first match on Court Philippe Chatrier.

“Very often that’s the kind of match she plays against other girls,” said the Frenchwoman. “So I tried to focus on having positive thoughts, and I thought to myself, ‘Okay, I have played boys and it can’t be worse’.

“She doesn’t come from another planet, so if I can move well and I can hit my ball well, there is no reason she should win 6-0 6-0.”

Next Serena will play Spaniard Garbine Muguruza then after that a clash against Venus beckons.

The 33-year-old had a tough draw against Swiss Belinda Bencic, virtually half her age and last year’s junior champion here and at Wimbledon.

The 17-year-old, who was two months old when Venus played her first French Open, has made rapid strides in the senior game and is already ranked in the top 100.

Her career has been overseen by Melanie Molitor, the mother of Martina Hingis, who was courtside to watch the teenager.

Bencic matched Venus for virtually the whole of the first set but the veteran’s extra power eventually told and she ran away with the second to win 6-4 6-1, her first victory at Roland Garros for two years.

Third seed Agnieszka Radwanska had the honour of being the first winner at this year's tournament with a 6-3 6-0 victory over Zhang Shuai of China.

Neither player held serve until Radwanska made it 5-3 in the opening set, but after that the Pole, a quarter-finalist for the first time last year, was untroubled.

Eighth seed Angelique Kerber, 14th seed Carla Suarez Navarro and Daniela Hantuchova are also through.

On Monday, 2012 champion Maria Sharapova begins her campaign against Ksenia Pervak in the opening match on Court Philippe Chatrier while Petra Kvitova and Jelena Jankovic are also in action.

FRENCH OPEN RESULTS MEN'S FIRST ROUND (4) Roger Federer (Switzerland) bt Lukas Lacko (Slovakia) 6-2 6-4 6-2 (6) Tomas Berdych (Czech Republic) beat Peter Polansky (Canada) 6-3 6-4 6-4 (8) Milos Raonic (Canada) beat Nick Kyrgios (Australia) 6-3 7-6 (1) 6-3 (10) John Isner (US) beat Pierre-Hugues Herbert (France) 7-6(5) 7-6(4) 7-5 (13) Jo-Wilfried Tsonga (France) beat Edouard Roger-Vasselin (France) 7-6(4) 7-5 6-2 (15) Mikhail Youzhny (Russia) beat Pablo Carreno (Spain) 3-6 1-6 6-3 6-4 6-0 (22) Jerzy Janowicz (Poland) beat Victor Estrella (Dominican Republic) 6-1 6-4 6-7(6) 6-4 (31) Dmitry Tursunov (Russia) beat Potito Starace (Italy) 6-1 7-5 6-2 Sam Querrey (US) beat Filippo Volandri (Italy) 7-6(3) 6-4 6-3 Diego Schwartzman (Argentina) beat Gastao Elias (Portugal) 6-4 6-2 7-5 Jarkko Nieminen (Finland) beat Michal Przysiezny (Poland) 6-7(7) 6-4 6-7(3) 6-3 6-4 Radek Stepanek (Czech Republic) beat Facundo Argueello (Argentina) 6-7(8) 3-6 6-4 6-3 6-2 Aleksandr Nedovyesov (Kazakhstan) beat Somdev Devvarman (India) 5-7 6-3 7-6(4) 6-3 WOMEN'S FIRST ROUND (1) Serena Williams (US) beat Alize Lim (France) 6-2 6-1 (3) Agnieszka Radwanska (Poland) beat Zhang Shuai (China) 6-3 6-0 (8) Angelique Kerber (Germany) beat Katarzyna Piter (Poland) 6-3 6-1 (14) Carla Suarez Navarro (Spain) beat Yuliya Beygelzimer (Ukraine) 7-5 7-5 (29) Venus Williams (US) beat Belinda Bencic (Switzerland) 6-4 6-1 (31) Daniela Hantuchova (Slovakia) beat Jovana Jaksic (Serbia) 2-6 6-2 6-4 Anna Karolina Schmiedlova (Slovakia) beat Zheng Jie (China) 6-7 (2) 6-3 6-4 Ajla Tomljanovic (Croatia) beat Francesca Schiavone (Italy) 6-3 6-3 Garbine Muguruza Blanco (Spain) beat Grace Min (US) 7-5 7-6(6) Yvonne Meusburger (Austria) beat Amandine Hesse (France) 3-6 6-3 6-4 Monica Niculescu (Romania) beat (25) Kaia Kanepi (Estonia) 5-7 6-3 6-1 Claire Feuerstein (France) beat Olga Govortsova (Belarus) 6-1 7-5 Anna Karolina Schmiedlova (Slovakia) beat Zheng Jie (China) 6-7(2) 6-3 6-4