Andy Murray will open his Madrid Masters campaign against Nicolas Almagro – conqueror of Rafael Nadal on clay last month – on Wednesday night.
Murray, 27, last played in Britain’s Davis Cup defeat by Italy in April.
Almagro, 28, ended world number one Nadal’s 41-match winning streak at the Barcelona Open two weeks ago.
“That will be an extremely tough match, definitely one of the hardest first-round matches you could get as a seed,” Murray told BBC Sport.
“He obviously beat Rafa a few days ago and he’s playing in Spain in front of a home crowd, so it will be very tough.”
Murray and Almagro will meet for the fifth time, not before 19:00 BST, with the Scot 3-1 ahead in previous meetings but having lost their only previous clash on clay at the 2008 French Open.
It will also be the first time Murray has played since learning of the death of fellow Scot and childhood friend Elena Baltacha on Saturday.
The Wimbledon champion’s last match on the ATP Tour was a straight-sets defeat by Novak Djokovic in Miami on 26 March and he heads into the clay-court season ranked eighth in the world.
The Scot’s slide down the rankings followed his decision to have back surgery last September, ending his 2013 season prematurely, and this week he is defending the points earned from a run to the quarter-finals in Madrid 12 months ago.
“The rankings just now – that will even itself out by the end of the year,” said Murray.
“I missed a large part of last year with the surgery. There are a few big tournaments after the US Open. Hopefully if I play good tennis, my ranking will improve. You need to win matches to improve your rankings, so we’ll see.
“These next few weeks and in particular Roland Garros, as I missed it last year, is a goal of mine.
“I’d like to be playing my best tennis by the time I get there and the best way to do that is by winning matches in these events to build the confidence up and get used to playing on clay again.”
Murray continues to search for a replacement for Ivan Lendl after splitting with the coach who guided him to two Grand Slam titles and an Olympic gold medal in March.
He hopes to have someone in place before the French Open starts on 25 May, but added: “It depends how I do the next few weeks.
“If I do well, I’m not going to have that much time; if I don’t do so well then I’ll have a little bit more time to think about it and chat to people.”
Roger Federer had been a possible quarter-final opponent for Murray in Madrid but the Swiss withdrew on Tuesday to be with his wife Mirka, who has given birth to the couple’s second set of twins.
Murray is now the highest seed in his quarter of the draw, with Nadal a possible semi-final opponent.
BBC SPORT
