Indian Wells - Two-time Grand Slam champion Andy Murray was searching for answers on Wednesday after an inexplicable third-set fade against Milos Raonic in the fourth round at Indian Wells.
Scotland's Murray, the world number six who is seeded fifth in the first ATP Masters of the year, appeared to be in control after breaking the mighty Raonic serve for a 2-1 lead in the third set.
But the Scot was broken to love in the next game, and broken again to fall 4-2 down amid a plethora of unforced errors, finally succumbing 4-6, 7-5, 6-3.
"It was poor," Murray said.
"To get broken two consecutive times in that situation isn't good enough. I played poor tennis at that stage.
"I didn't make enough balls, missed easy shots -- really easy shots. There were some where he was standing in the net and I just had to hit it to the other side. Missing shots like that."
Murray, 26, has yet to reach a final since having back surgery in September.
But he said he played good matches in losing to Roger Federer in the quarter-finals of the Australian Open in January and to in-form Croatian Marin Cilic in the quarters at Rotterdam.
He arrived in the California desert off a semi-final run in Acapulco, encouraged that at last he felt truly match fit.
But he had to dig deep in each of his first two matches here, losing the first set against both Lukas Rosol and Jiri Vesely.
"It was clearly patchy," Murray said of his performance in a tournament in which he hasn't made it past the quarter-finals since his runner-up finish in 2009.
Against a player like 10th-seeded Raonic, any lapses are more costly, Murray said, because the Canadian can win so many easy points with his serve.
"I'll need to have a think about it and have a look at what happened," said Murray, who will try to turn things around at the Miami Masters starting next week.
"But, you know, there wasn't a huge explanation for it, because the shots I was missing, it wasn't like one shot in particular when I'd miss every shot.
"First-serve percentage dropped, missed a lot of backhands, missed a few easy forehand passes as well."
With his back feeling fine, Murray mused that such a sudden drop in form at the crucial point of the match was due to something more intangible.
"It's going to come down to confidence," Murray said.
"There's no other explanation for missing those shots."