Andy Murray made a successful start to his reunion with coach Ivan Lendl as the defending champion battled to a 7-6 (10/8), 7-6 (7/1) victory over Nicolas Mahut at Queen's Club on Tuesday.
Murray is bidding for a record fifth title at the Wimbledon warm-up event and the world number two ignored the slippery conditions on a rainy day in west London to advance to the second round in one hour and 50 minutes.
He will play Britain's Aljaz Bedene or France's Benoit Paire for a place in the quarter-finals.
Earlier, Stan Wawrinka suffered more misery on grass despite the addition of new coach Richard Krajicek as the Swiss second seed crashed to a 6-2, 7-6 (7/3) first round defeat against Fernando Verdasco.
Murray enjoyed a golden two-year period with Lendl that brought him the Wimbledon and US Open titles and an Olympic gold medal before they parted in 2014 due to the Czech's refusal to increase the amount of time they worked together.
The 29-year-old had hankered after a reunion ever since and, although there is plenty of room for improvement, he was pleased with the way he subdued the dangerous Mahut in the first match of the second Lendl era.
"It was tough. Nico is a very accomplished grass-court player," Murray said.
"Ivan doesn't give any signs during the match. He has a pretty straight face. But it is great to have him back and, working with Jamie Delgado, I think it is a pretty strong team. Hopefully they can help me win more big events."
"It's great to have him [Ivan] back as part of the team, obviously," Murray said. "It's good to chat. When we were chatting sort of before the match, it didn't feel strange. It felt like it did before. I think it's a positive thing."
Mahut had won just one of his previous five meetings with Murray, but the French world number 51 had won the grass-court event in 's-Hertogenbosch on Monday and finished as Queen's runner-up in 2007.
In contrast, Murray was playing for the first time since losing his maiden French Open final against Novak Djokovic nine days ago.
Murray felt so frustrated and run down when he left Paris that he didn't touch a racket for the next five days.
So inevitably there were a few signs of rust as Murray acclimatised to the grass and Mahut landed the first blow when he broke for a 3-2 lead.
But Murray broke back in the next game and Lendl, hidden behind sunglasses and a baseball cap, was typically impassive as he watched the Scot edge through.
Despite being ranked fifth in the world and having won two Grand Slam titles, Wawrinka has never triumphed at a grass-court tournament and he added 1996 Wimbledon champion Krajicek to his coaching team last week in a bid to find some answers.
But, with Manchester United legend David Beckham and his son Romeo watching, the early returns on the partnership weren't promising as world number 53 Verdasco set up a second round meeting with Australia's Bernard Tomic, who beat South Africa's Kevin Anderson 6-3, 6-4.
"Grass is always a challenging surface for my game. I need quite a lot of practice to play my best. I tried today with what I had, but I need more time to get to my level," Wawrinka said.
"When the grass is quite fast, you need to be the aggressive player. Fernando was better than me today."
Elsewhere, 2012 Queen's champion Marin Cilic defeated Spain's Feliciano Lopez 4-6, 6-3, 6-4 and next plays Serbia's Janko Tipsarevic, who defeated 2014 Queen's winner Grigor Dimitrov 7-6 (8/6), 4-6, 6-3.
Spanish sixth seed Roberto Bautista Agut ground out a 7-6 (7/2), 6-7 (4/7), 7-6 (7/1) victory over 2010 Queen's winner Sam Querrey and next faces Donald Young.
Milos Raonic's first match since hiring American great John McEnroe as his coach was suspended at 6-7 (5/7) 6-4 due to bad light after the Canadian third seed drew level with Australia's Nick Kyrgios.