Bill Haas has so many family connections to the Masters that he must bleed hunter green. His family crest should be crossed pimento-cheese sandwiches. Most call this tournament the first major of the year. The Haas clan just calls it spring break.

After Haas finished putting up his first sub-70 score in 17 tries at the Masters — his 68 good for the first-round lead — he was obliged to spell out all those who have gone before him.

Great-uncle Bob Goalby won the 1968 Masters.

His dad, Jay, appeared in 22 of them, his best finish a third in 1995.

Uncle Jerry Haas made one trip, in 1985.

Another uncle on his mother’s side, Dillard Pruitt, was in two others in the 1990s.

“It’s something I think we are very proud of to have that many members of our family to be able to tee it up here at Augusta,” Haas said. OK, just this once, you may call Augusta National the House of Haas.

Haas broke out his ‘A’ game — maybe even his double-A game — Thursday. His was a round full of bounce-back, responding to his only two bogeys on Nos. 1 and 17 with immediate birdies.

A five-time PGA Tour champion with more than $18 million in winnings, Haas has had better days on a course than Thursday. The best of them all was at East Lake in 2011, when he pulled par from the water on the third playoff hole to win the Tour Championship/Fed Ex Cup.

There is, after all, much more golf to play. “I was leading last week after the first round and finished 37th,” Haas said. “You’ve just got to go out there and keep playing golf, try to hit that fairway on No. 1 tomorrow.”

And besides, dad’s still done better. Jay’s best round here was a 64 the year he finished third.

It’s not like Bill grew up consumed by the aura of the place, which may be beneficial now. It was pretty and history-drenched and all that, but he had a bad case of tunnel vision.

“I would follow my dad every shot, every day, and then I went to the range with him or I went home. I wasn’t interested in the Masters; I was interested in my dad’s score at the Masters.”

Time reversed the roles. Now it’s Jay following his boy’s every step here, from the practice tee to the course to the house they’re renting for the week.

Oh, but many a father’s son is chasing Haas.

The Masters champions from the preceding two years, Adam Scott and Bubba Watson, are just a stroke back. So is the fellow who lost in a playoff to Watson in 2012, Louis Oosthuizen.

The former champs pulled up on Haas’ bumper by different means.

Scott had to scramble, recovering from his first-ever visit to Rae’s Creek on the par-3 12th and the double-bogey that ensued. He let himself get swept away by the rousing reception he received from the gallery as he walked to 12, he said, and consequently lost focus on the tee shot. Adulation can be such a heavy burden. He also three-putted both the par-5s on the back side.

Otherwise, “I feel like I’m playing really well,” he said.

Watson, the guy who supposedly sprays it around like an untended fire hose, had perhaps the most under-control round of the day. He led the field in greens in regulation (16), which explained his bogey-free afternoon. The two greens he missed were by six inches and three feet.

“I don’t want to give my secret, but I’m trying to just hit greens,” Watson said, as if going all Edward Snowden with that startling revelation.

“If I can hit greens, that means I’ve hit good tee shots and I hit good iron shots. I’m just trying to make par from there and throw in a birdie here and there. And that’s what I did today.”

In all, there were 19 rounds under par. The climate suggested there could have been more low scores than that, what with blue skies, mild temps and a fair wind. But the pin committee fought that notion.

“(The pins) are all tough,” Steve Stricker (72) said. “All tough in their own way.”

The under-par club included four from the record group of 24 first-time Masters players: Jonas Blixt and Jimmy Walker (70); Jordan Spieth and Stephen Gallacher (71). The possibility of a one-and-won scenario is still in play.

Well on the other side of par was the most decorated player in the field, the largest personality here, with Tiger Woods on the shelf. While it is always risky to declare the competitive demise of a player on Thursday, go ahead and sound the first notes of “Taps” over Phil Mickelson’s pursuit of a fourth green jacket.

Throughout Mickelson’s 83 rounds at the Masters, he has played seven holes cumulatively under par. Two of those he butchered Thursday on the way to a 4-over 76. Mickelson’s renowned short game deserted him on the par-4 seventh when he chipped off the green and three-putted coming back, recording his first-ever triple-bogey 7. He took double bogey on the par-5 15th when he dumped his third shot in the water.

The groans resounded throughout the House of Haas.