Roger Federer began his
Third seed Federer was 6-3, 3-0 ahead when the Ukrainian retired from the first round match on Center Court with an ankle injury after just 43 minutes.
"It feels great to be back on Center Court," said Federer who recorded his 85th match win at the All England Club, passing the mark he shared with Jimmy Connors.
Federer, who hit his 10,000th career ace in the eighth game of the first set, will face either Dusan Lajovic of Serbia or Greek qualifier Stefanos Tsitsipas for a place in the last 32.
Dolgopolov had called the trainer at the end of the first set, complaining of an ankle injury.
Ironically, three-time champion Novak Djokovic had earlier also benefitted from an early retirement when Slovakia's Martin Klizan quit at 6-3, 2-0 down after 40 minutes.
"Clearly I was hoping that Alexandr was feeling better today but he's had a rough one this year. He's had to pull out of a lot of matches," Federer said.
"He tried. For me obviously I'm very happy to be back and getting another win here is great news."
The 35-year-old Federer, seeking a 19th Grand Slam title and bidding to become the oldest champion at the All England Club, played down the tag of favourite for a trophy he last lifted in 2012.
"Just because I haven't played the clay court season doesn't make me the favorite," he said.
"You would think that somebody who has played well, like Rafa (Nadal) on the clay courts, he would be feeling really good about his chances here and I'm sure he does feel that way. The same for (defending champion) Andy Murray, same for Djokovic.
"Everybody's got a chance to win Wimbledon and for me it's no different. I already achieved my dream to be back here healthy. Now we'll see how far I can go."
Milos Raonic was back in the old routine as last year's Wimbledon runner-up advanced to the second round with a 7-6 (7/5), 6-2, 7-6 (7/4) win over Jan-Lennard Struff. Big-serving Raonic became the first Canadian man to make a Grand Slam final with his impressive Wimbledon run 12 months ago before losing the title match to Andy Murray.
Juan Martin del Potro moved to within one victory of a potential Wimbledon rematch against Novak Djokovic. The injury-prone Argentine slipped all over Court Two on Tuesday before he completed a 6-3, 3-6, 7-6 (7/2), 6-4 win over Thanasi Kokkinakis of Australia.
Del Potro's reward is a second round clash against unpredictable Latvian Ernests Gulbis who brushed past Victor Estrella of Dominica 6-1, 6-1, 6-2.
Japan's Taro Daniel was knocked out in four sets by Mikhail Kukushkin of Kazakhstan. Daniel lost 4-6, 6-4, 7-6 (4), 6-2.
In the women's draw, Karolina Pliskova underlined why she is the bookmakers' favorite to win Wimbledon as the world number three crushed Evgeniya Rodina 6-1, 6-4 in the first round. With defending champion Serena Williams sidelined due to the impending birth of her first child, there is a power vacuum at the top of women's tennis and Pliskova could be poised to fill it.
The 25-year-old Czech emerged as a potential star when she reached the U.S. Open final last year and she has followed up on that breakthrough by making the French Open semi-finals last month.
Caroline Wozniacki overcame a second-set wobble to book her spot in the second round. The Danish fifth seed beat Hungary's world number 42 Timea Babos 6-4, 4-6, 6-1 in an hour and 42 minutes.
Japan's Misaki Doi went out in the first round, losing to Kirsten Flipkens of Belgium 6-4, 6-3.
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