World number one Andy Murray can find "no reason" why he is "struggling" with his form following defeat in the second round of the Italian Open.
The 30-year-old lost 6-2 6-4 to Fabio Fognini in Rome and has now won one title from eight events in 2017.
The French Open begins on 28 May but Murray has only reached one semi-final in his last four clay court events.
"I'm just not playing good tennis and need to try to work out how to turn it around," he said. "I believe I will."
He added: "The last couple of weeks have definitely been a struggle and a long way from where I'd like to be.