These two have split their two matches on clay.
First they played each other virtually to a standstill in a pulsating battle for Olympic gold in Rio.
Del Potro served at 1-1 but Almagro did not return it and instead collapsed to the the ground seemingly in pain.
Sport is not only about competitiveness but also sportsmanship and Argentine Juan Martin del Potro has every bit of it in him.
Murray and del Potro played each other twice previous year and both were epics.
"I said to him, Try to be calm". I'm capable of winning that match.
"He's, in my opinion, one of the best players in the world when he's fit and healthy".
"Juan Martin has come back from some injuries and had some tough draws".
Klizan's play had become a lot more erratic, the 27-year-old no longer finding the mark so often with his forehand and appearing bothered again by his calf. He lost to Raonic in Delray Beach, Miami I think he lost to Roger.
His opponent, a hotheaded Slovakian now ranked at 50 by the ATP, endured an eventful start to the tournament earlier this week when wildcard Laurent Lokoli refused to shake his hand after claiming that he had exaggerated a calf injury.
Del Potro, playing in Paris for the first time in five years, went through to the last 32 after Nicolas Almagro retired in tears with a knee injury.
"I know what injuries are all about". It's not a source of concern'.
The world number nine will face South Korean Hyeon Chung for a place in the last-16. "I feel like I've way underdone coming into the French".
'Andy is one of the favourites to win the tournament.
"I tried to find good words for that moment". There's no point in having a shot like that and not using it. "Hey I'm the youngest of 5 I've always tricked all of them what can I say!" And earlier in the tournament, Petra Kvitova and Kristina Mladenovic won victories that had meaning beyond the scoreboard, representing possible new steps in their careers.
Murray suffered a shock fourth-round exit at the Australian Open and his struggle for form was further highlighted by premature exits at Monte Carlo, Madrid and Rome in the build-up to Paris. Anderson next faces Britain's Kyle Edmund. "It will be very tough".
"And I think that kind of helps everyone". "I only had a week practice, so I am just very happy to be in the third round".
He continued to do things the hard way, but Klizan's resistance finally came to an end in the tie-break and Murray took his second match point with one of his best shots, somehow digging out a forehand victor. My body feels really strong and healthy.