Patience has been the key to Andy Murray's new-found prowess on clay, according to his French Open opponent Radek Stepanek.
The world number two goes into the year's second grand slam as one of the big favourites to lift the title at Roland Garros.
Having failed to make a final on the surface until last year and managing just one victory over a top-10 player, Murray can now boast three titles and wins over both Novak Djokovic and Rafael Nadal.
Stepanek said: "His improvement on clay in the last years was tremendous. I think Andy was missing patience in the years before. I think he now has everything settled down for him on clay.
"He feels the game right. His last results are proof of that. He will come to the tournament with a lot of confidence."
Stepanek is well placed to assess Murray's game having played him earlier this month in Madrid, when he took a set off the Scot.
The Czech, a self-confessed awkward player, can boast two wins from eight previous meetings with Murray and is a player the 29-year-old would have hoped to avoid when the qualifiers were placed.
At 37, Stepanek is not just the oldest player in the field but the oldest to play in the main draw of a grand slam since Jimmy Connors competed at the US Open in 1992 just short of his 40th birthday.
"It's not that far," said Stepanek, who is ranked 129th. "It's nice to be in a group with Jimmy Connors who has done so much for the game. I think he played with the same amount of emotions as I do and that's what I love about him and obviously it's going to be a challenge maybe to be older than him and be here still."
Stepanek, once a top-10 player, was out for eight months at the end of 2014 and the start of 2015 because of a sciatic nerve problem but retirement has never been on his radar.
He said: "People ask me, 'Why do you still want to play qualifying at your age after you have been at the top?' The love for the game is there, no matter where I'm standing or what the number of my ranking is.
"I was out for eight months so I'm very pleased for every minute I can spend on the court. My situation 12 months ago wasn't good. As long as I am healthy, I always say that, when the hardware is good, I have the software ."
Weather permitting, Murray and Stepanek will play in the fourth match on Philippe Chatrier. Rain dominated the opening day, with only 10 matches able to be completed.
Heather Watson's match against Nicole Gibbs was called off with the American a break up early in the deciding set.
Two other British players are scheduled to play on Monday, with Kyle Edmund taking on Nikoloz Basilashvili and Naomi Broady facing Coco Vandeweghe on her French Open debut.