Kuznetsova beats Wozniacki under roof LONDON — Defending champion Serena Williams racked up her 80th Wimbledon victory Tuesday while Andy Murray raced through before rain brought action at the All England Club to a soggy halt. World No. 1 and six-time champion Williams, bidding for a record-equaling 22nd Grand Slam title, battled to a 6-2, 6-4 win over Swiss qualifier Amra Sadikovic, ranked at 148 in the world. She will face fellow American Christina McHale for a place in the last 32. "I would be lying if I said I feel fresh, but I don't feel fatigue. I feel real hungry, super motivated, extremely ready to do the best," said the American star, whose mother Oracene Price was watching from the front row of the Centre Court Royal Box. However, not everyone gave her the royal seal of approval. "It was one of the worst serving efforts I've seen from Serena. This is what is giving other players hope," said US legend John McEnroe, commentating for the BBC. Top seed Williams won her 21st major at the All England Club 12 months ago by beating Garbine Muguruza. But her hopes of going level with Steffi Graf's Open era record of 22 has stalled since that day. She went down to a US Open semifinal loss to Italy's Roberta Vinci followed by defeat in the Australian Open final to Angelique Kerber and then to Muguruza in the French Open final earlier this month. [caption id="attachment_65751" align="alignright" width="300"] Great Britain's Andy Murray celebrates after winning his match against Great Britain's Liam Broady in Wimbledon, England, Tuesday. — Reuters[/caption]Murray, the 2013 champion, made a flying start to his bid for a second Wimbledon title as the world No. 2 crushed compatriot Liam Broady 6-2, 6-3, 6-4. The 29-year-old brushed aside the world No. 235 and will next play Taiwan's Lu Yen-hsun. "The first match is always tricky and it was pretty breezy out there at the beginning," said Murray. "We've practiced together in the past. It's not easy playing someone you know, so I did ok." Minutes after Murray had completed victory, heavy rain brought a halt to action on all courts except Centre Court where the roof was closed. In a first-round contest played under the Centre Court roof, Svetlana Kuznetsova beat Caroline Wozniacki 7-5, 6-4 in a match between two former No. 1 players. The 13th-seeded Russian, playing in her 13th Wimbledon, held off a late charge from the 45th-ranked Wozniacki, who was unseeded at a Grand Slam for the first time in eight years. Kuznetsova has reached the Wimbledon quarterfinals three times — in 2003, 2005 and 2007. Earlier, Swiss fourth seed Stan Wawrinka defeated American teenager Taylor Fritz 7-6 (7-4), 6-1, 6-7 (2-7), 6-4 to set-up a second round blockbuster against Juan Martin del Potro. Injury-plagued del Potro, a former US Open champion, is playing in his first Grand Slam since the 2014 Australian Open after undergoing three wrist surgeries. Del Potro made the second round by beating France's Stephane Robert 6-1, 7-5, 6-0. The Argentina star is ranked at 165 but made the semifinals at Wimbledon in 2013, while Wawrinka has twice been a quarterfinalist. Nick Kyrgios, the Australian 15th seed, beat Czech wildcard Radek Stepanek, at 37 the oldest man in the draw, 6-4, 6-3, 6-7 (9-11), 6-1. He next faces German wildcard Dustin Brown who got past Dusan Lajovic of Serbia 4-6, 6-3, 3-6, 6-3, 6-4. Hoping for a sporting clean sweep, Richard Gasquet and Jo-Wilfried Tsonga carried the French flag into the second round with straight-sets wins over Britain's Aljaz Bedene and Spain's Inigo Cervantes. Seventh seed Gasquet used his trademark backhand to good effect to see off the British No. 2 6-3 6-4 6-3, although both players pulled off strokes that were at times things of beauty during their baseline rallies. Tsonga, back in action for the first time after retiring from the French Open with a groin injury, shook off the cobwebs of a close first few games to beat the Spaniard, ranked 75th in the world, 6-4 7-6(5) 6-4. On Monday, Roger Federer began his 18th consecutive Wimbledon challenge with a straight-sets win over Argentina's Guido Pella — but it was never straightforward for the Swiss as he won 7-6(5) 7-6(3) 6-3. Ninth seed Madison Keys was a 6-3, 6-1 victor over Germany's Laura Siegemund while Romanian fifth seed Simona Halep, a semifinalist in 2014, beat Slovakia's Anna Karolína Schmiedlova 6-4, 6-1.