Andy Murray takes up-and-down road to U.S. Open semifinals

Andy Murray rallied from an ugly start to dispatch Marin Cilic in four sets. (Getty Images) Andy Murray is like a box of chocolates. You never know what

Andy Murray rallied from an ugly start to dispatch Marin Cilic in four sets. (Getty Images)

Andy Murray is like a box of chocolates. You never know what you're going to get. And what you get could be horribly messy.

For those who like their tennis unpredictable -- and yes, these people do exist -- there can be no player more entertaining on the men's tour right now than Murray. Invest in a large movie comb0, settle into a cushy seat, and watch as the gold medal winning Brit stalks out on to the court with his Head racket in hand, looking like a guy who's trying to play off the fact that he just rolled out of bed 15 minutes ago and forgot he had a match. That much you can count on. The rest? Well... it's complicated.

Murray's road to his third U.S. Open semifinals, clinched by a 3-6, 7-6 (4), 6-2, 6-0 comeback win over Marin Cilic on Wednesday, hasn't been the confidence inspiring performance that many expected. The book on Murray was that he had turned a corner, rebounding from his gutting loss to Roger Federer in the Wimbledon final by beating him so decisively a few weeks later at the Olympics. It may very well be that he has, but the five matches he's played in New York have been more two steps forward, one step back than anything else.

He opened his tournament with a straight set win over Alex Bogomolov Jr., yet struggled to hold serve and even keep the ball inside the court. Over the two and a half hour match, Murray served under 50 percent and sprayed 31 unforced errors. In the end, a win is a win and Murray emphasized as much to his head-scratching inquisitors after the match. Two days later, he was back to his old self, dominating Ivan Dodig in a dominant 6-2, 6-1, 6-3 win under the Arthur Ashe Stadium lights. Murray was all good, you guys. Nothing to see here. Move along.

But then there was the sluggish third-round match against Feliciano Lopez. Struggling under the heat, Murray survived by winning three tiebreaks, beating the talented lefty 7-6 (5), 7-6 (5), 4-6, 7-6 (4). For much of the match he looked on the verge of physically tapping out, almost slinking along trying to find the energy to compete from point to point. The margins were small and when Murray needed it in the tiebreaks, it was there.

Yet after those up-and-down matches, Murray seemed to put any concerns to rest with his showcase win over Milos Raonic in the fourth round. If this was a UFC battle, Murray was the master of submission, absorbing everything Raonic threw at him and wowing the crowd with his speed and shotmaking. It was Murray's special brand of aggressive counter-punching at its finest.

And so his week of resplendent highs and grueling lows culminated in a quizzical display against Cilic. A player against whom he held a 7-1 head to head advantage, Murray came out and played some awful tennis. The match was originally scheduled for Ashe but was moved once the women's quarterfinal ran a full three sets. The switch seemed to unsettle Murray, who complained about the quickness of the court and grew so frustrated at one point that he threw his racket violently to the ground, something we don't often see from Murray.

"I didn't start too well," Murray admitted. "He started off well. He was playing close to the baseline. I have always found that court tricky to play on. I have had a lot of tough matches on it. Yeah, it took me a while to get used to it. I think when the conditions slowed down a bit and started to get a bit darker, that helped me."

Help him it did. If there's one pattern to glean from Murray's first five matches, it's that he seems to struggle during the day and excel at night. As the sun began to set and temperatures dropped, conditions slowed on Armstrong, allowing Murray to come back from 1-5 down in the second set to reel off five straight games and win the set in a tiebreak and go on to win 12 of the last 14 games of the match. Murray's ability to tighten up his game coincided with an epic choke by Cilic, who wilted as Murray fought back.

Given his pattern for the tournament, Murray will hope that his semifinal match against either Roger Federer or Tomas Berdych is scheduled at night, when he's played his best tennis in New York. But either way, it's difficult to know what to expect from Murray when he takes the court for his next match. Perhaps the best thing we can say about Murray is that regardless of his form, day or night, fast court or slow, he's found a way to win. At this point, that's all that matters.