Updated

By Mark Lamport-Stokes

BETHESDA, Maryland (Reuters) - While Congressional's Blue Course has been described by the players as a fair but tough test for this week's U.S. Open, opinions are divided over the challenge of the daunting par-three 10th.

Measuring 218 yards off the back tee, the 10th will be the opening hole for half the field because of the U.S. Open's two-tee start, a sudden and rude awakening for players who have only just left the practice range.

"Starting a round on 10, I can't see too many tougher holes to start on, especially off that back tee," South African Ernie Els told reporters while preparing for Thursday's opening round.

"You might have to come off the range, hit your putts and then go to your first hole of the day, which could be a four-iron over water and a bunker at the back. That's an incredibly difficult start."

British world number one Luke Donald agreed.

"It's certainly a challenge," the straight-hitting Englishman said. "I suppose if I was given the choice I would have preferred to tee off on one early on.

"It's not too often you begin on a par three. It's just a different kind of feel, something you just have to deal with."

World number five Phil Mickelson described the 7,574-yard Blue Course as "a wonderfully fair test" and gave rave reviews of the picturesque 523-yard 18th with its peninsula green.

The 10th hole, however, was a very different matter for the American left-hander.

"As I was saying earlier about how 18 is a brilliantly designed golf hole, I think 10 is the exact opposite, because the average guy can't play that hole," four-times major champion Mickelson said.

"He can't carry that water and get it stopped on that green. So when I play that hole, three is a great score. I'll take three every day. If I happen to make a four, so be it."

REVAMPED 10TH

The revamped 10th hole has replaced the par-three finishing hole from the 1997 U.S. Open held at Congressional and plays in the opposite direction.

From an elevated tee, players will need to take great care with club selection to avoid a large pond in front of a back-to-front sloping green.

"You've got to take the front out of play, so you have to miss that hole long and you might hit a shot out of the bunker," said Mickelson, who is renowned for his magical short game skills.

"And I've spent some time out of that sand. I think I can get it up and down to most of those pins."

Mickelson had no complaints, though, about the par-three 10th being the opening hole for players in one of the first two rounds.

"It's fine being the first hole of the day because you're just trying to get into the flow of the round," the 40-year-old said. "Even though it's a tough shot, it's only one shot.

"You don't have to hit a drive and an iron shot. You just have to hit an iron shot where you can get up and down where you can make par or on the green."

Overall, Mickelson praised the course set-up by the United States Golf Association for this week's U.S. Open.

"It's a wonderfully fair test for such a difficult, long test," he said. "I thought it was very well done, and I'm looking forward to playing.

"What I like most about this course is that the hard holes are really hard and the easy holes are fairly easy. That provides opportunities for birdies and bogeys."

(Editing by Julian Linden)