|Venue: Queen's Club, London Dates: 13-19 June|
|Coverage: Live on BBC Two, Radio 5 live & 5 live sports extra, Red Button, Connected TVs and BBC Sport website. Click for more details|
Ivan Lendl said it felt as if he had "never stepped away" after watching Andy Murray mark the resumption of their coaching partnership with a win.
Lendl was in the players' box as world number two Murray beat Nicolas Mahut 7-6 (10-8) 7-6 (7-1) to reach the second round at Queen's Club.
"Andy and I have talked over the last few years," Lendl, who reunited with the Scot on Sunday, told BBC Sport.
"We've stayed in touch, and as you know, we parted on good terms."
Murray won the Olympics, the US Open and Wimbledon during his original spell with the Czech-born American, until Lendl decided in March 2014 that he no longer wished to spend sufficient time on tour.
The 56-year-old - an eight-time singles Grand Slam winner - is expected to work with Murray for up to 20 weeks a year.
He has never talked fondly about the travel involved, and says there is not one overwhelming reason why this feels the right time to return.
"Everybody asked me what was it that made you do it, and I can't answer that. I really don't know, there are so many factors in there," Lendl added.
"I can't say what changed it from 'not really' to 'yes'.
"I don't mind living out of a suitcase, and I don't mind the longer trips - let's say to London or to Australia - I just hate the ones from week to week where you spend five days somewhere, and you have to go to the airport again."
Lendl has already been 'welcomed back to the locker room' by his former rival Boris Becker, who has recently enjoyed huge success with Novak Djokovic.
Djokovic currently holds all four Grand Slam titles, and helping Murray beat the world number one is one of the principal reasons Lendl has been drafted back into the team.
"Everybody can improve in almost every area - even Novak," Lendl said.
"There are obviously things which we are going to work on which are more important than some others, but I'm definitely not going to be specific."
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