Jim Furyk has warned Waterford amateur Kevin Phelan not to let youthful enthusiasm get the better of him on his US Open debut.

And after a thrilling practice round with the 2003 champion and last year’s joint runner up Ricky Barnes, Phelan has had the good sense to listen.

The Florida-based Irish teenager, 19, had planned to play as many as four full practice rounds at the spectacular links on the Monterey Peninsula.

But he’s decided to heed Furyk’s advice and save his energy for the championship proper so he can give his major debut 100 percent.

Phelan revealed: “Jim told me not to do too much because a lot of young guys come out and practice too much and then they are tired for the tournament. So I will probably just play nine holes each day and take it easy a little bit.”

Furyk immediately took the Irish lad under his wing after a call from a mutual friend and told him to enjoy every minute of his first US Open experience.

“His golf coach called me and asked to get a round in with him and his caddie is the son of Mark McCumber, who I’ve known for a long time,” Furyk said after their round.”

Phelan was cool, calm and collected during his dream practice round with two of the PGA Tour’s top stars but he didn’t bombard them with questions.

“No, he was real quiet and shy,” Furyk said. “But he had a good little game and he’ll get a lot of experience this week.

“He seems like a good kid and I tried to give him a few pointers here and there.

“I told him to realise that he belongs here, that he fought for it and earned his spot, nobody gave it to him. I told him to make sure he had fun and not get too overwrought. 

“At that age I’d probably have tried so hard, I’d have forgotten to have a good time.

“Third part of it was not to wear himself out. He’ll probably try to play 72 holes. So I advised him to treated the way he would his normal college event and look around and learn because he’s got some of the best players in the world here.”

Phelan qualified for his US Open debut last week when he holed a flop shot for an eagle on the final hole of a 36-hole sectional qualifier at Hobe Sound in Florida.

He knows it won’t be easy to make the cut after a chat with Barnes, who shot rounds of 80 and 73 on his US Open debut here in 2000.

Phelan said: “It was great. I really enjoyed it and Ricky was great as well. He qualified for the US Open at Pebble Beach when he was the same age as me, 19, just after his first year at college. That was kinda cool.”