Ex-Champion Sees Tough Road for, Well, Everyone WIMBLEDON, England - The only certainty about Wimbledon 2013 is that the tournament is sure to continue staunchly avoiding predictability. Whenever you suspect that the cast-iron favorites are finally emerging through the carnage, the next day's play upends all expectations. One might as well spin the roulette wheel when it comes to picking the eventual champions. Or consult Pat Cash. The 1987 Wimbledon champion simply shook his head in bewilderment when he reflected on the events so far this fortnight. While he cautiously suggested that a Novak Djokovic-Andy Murray final is more likely than not, he also said that Djokovic could be in for some testing times over the next few days, particularly if Juan Martín del Potro defeats David Ferrer in the quarterfinals. "Djokovic has definitely the tougher run," Cash said. If del Potro's knee is O.K., which is the big question mark, he's going to be dangerous. He's a big hitter, he's done it before and he can really trouble these guys when he runs hot, especially when he's got nothing to lose and he swings away. Cash said he liked the eighth-seeded del Potro's chances against No. 4 Ferrer. "It's not Ferrer's favorite surface," Cash said, "he's just good at getting balls back. But the weather's going to play a big part. Del Potro's so strong he can hit a winner in any conditions, but if it's slower, he'll have to do a lot of running on his dodgy knee, which may be a problem. Cash was impressed with how well Djokovic dealt with Tommy Haas on Monday, and he doesn't see Tomas Berdych repeating his shocking victory in the 2010 semifinals. "I don't think Berdych is playing that well," Cash said. He did beat him a few years ago, but Djokovic wasn't the same player as he is now. Djokovic was not well physically then, he was exhausted after a set. So it is advantage Murray? At the start of the tournament his path to the final looked devilishly tough, but he has watched as, one by one, his biggest rivals have fallen by the wayside. Cash cautioned that that may work against him should it come to a showdown against Djokovic in the final on Sunday. "If Djokovic beats Berdych and del Potro without expending too much energy, then you'll think, yeah, he's the favorite, while if Murray beats Verdasco and Janowicz, it's a bit unknown how well he really is playing," Cash said. In this wacky Wimbledon, Jerzy Janowicz and Fernando Verdasco are unlikely quarterfinalists. "I think Murray needs some tough matches along the way," Cash said. Just sticky matches, they don't necessarily have to be five-setters. Djokovic's serving isn't normally the focus of much attention, but it has been a revelation so far this fortnight. "The great thing about these guys is that they're constantly working on their game, and it's the little things here and there which end up making a big difference," Cash said. Cash noted that "the elbow angle has changed over the years on Djokovic's serve. It was very bent and I think he's straightened it up. He's always had a good ball toss trajectory, good reach and a good throw, but his problems in the past have mainly been about his elbow bend and how far behind him it came. Cash added: "His adjustments have added more consistency. He's always had the power.