If anyone needed reassurance as to the state of Andy Murray's back, they need only have had a look at the practice courts moments after his second-round victory over Lukas Rosol at the BNP Paribas Open in Indian Wells.
Despite taking one hour and 45 minutes in the heat of the Californian desert to beat the big-hitting Czech in three sets on Saturday, the Scot felt it necessary to head back out immediately to practise.
It is a clear indication that Murray is feeling no ill-effects as he takes part in the first Masters 1000 event of the year, as does the relatively short time it took him to turn up for his post-match media duties.
"I certainly wouldn't be in here [the interview room] this quickly," said Murray. "I went out to hit some balls after my match too, which I would not have done six months ago because I would have been sore. I'm feeling much better."
Murray was also competing in the doubles with Yorkshire's Jonathan Marray, who won the 2012 Wimbledon men's doubles title, but they lost 7-6 (7-1), 6-3 last night to Alexander Peya, of Austria, and Brazil's Bruno Soares in the second round.
"I'm waking up not sore, which is nice," said Murray. "Practice isn't compromised because I can barely move; that's the biggest thing for me just now. I feel like I can play each day and not worry about it."
Murray will play for the fourth successive day today when he takes on 20-year-old Czech Jiri Vesely, a former junior world No.1 who has made steady progress to his present career-high ranking of 77.
While Murray is focused on one match at a time, many are already looking forward to a long-awaited potential encounter with world No.1 Rafael Nadal in the quarter-finals. Despite the pair having claimed four of the last six grand slams, they have not played one another since October 2011. Reaching the last eight at least would represent a successful week for Murray. Currently world No.6, it would ensure he defends his ranking points from last year, as well as offering the chance of a thorough test against the reigning champion.
Murray's older brother Jamie made an unsuccessful return from a pelvic injury as he and his Australian partner John Peers lost to the Frenchmen Julien Benneteau and Edouard Roger-Vasselin 6-3, 4-6, 10-5 in the first round on Saturday. Colin Fleming and Ross Hutchins yesterday beat Jean-Julien Rojer, of Netherlands Antilles, and Romania's Horia Tecau 5-7, 7-6 (7-4), 10-8.