Hale Irwin, who lost in a playoff last year, Mark McNulty, Bobby Wadkins and Brad Bryant are tied for fourth place. The quartet each posted rounds of 6-under-par 66 at Augusta Pines Golf Club.
Haas, technically a Champions Tour rookie because he only played three events last year, flew out of the gate on Friday with an eagle at the second hole. He parred his next seven holes to make the turn at 2 under par.
Last week's winner caught fire on the back nine. He drained a 15-foot birdie putt, then rolled in a 12-footer for birdie at the 11th. Haas continued the fine form with a 10-foot birdie putt at No. 12, then tapped in a short birdie putt at 13 for four in a row.
Haas did not give himself many good looks for birdie the rest of the way until the par-5 closing hole at Augusta Pines. He reached the green in two and two-putted from 46 feet for birdie and a share of the lead.
'I played very well today from tee to green,' acknowledged Haas, who has split time over the Champions Tour and PGA Tour this season. 'I hit a lot of good shots and had a lot of opportunities.'
Ireland's Smyth was steadier than Haas on the front nine. He collected birdies at the second, fourth and sixth holes to make the turn at 3-under-par 33.
Smyth made his move up the leaderboard with strong play at the beginning of his back nine. He tallied three birdies in a row from the 10th, but, like Haas, never gave himself great chances at birdies.
At the par-5 closing hole, Smyth landed on the putting surface with his second and lagged his eagle try inside 4 feet. Smyth converted the birdie putt for his share of the lead.
Smyth's high position so far is somewhat shocking considering the recent change of tools. He has new irons, a new driver and returned to a short putter in the last six weeks.
'The last five or six weeks, I've gone flat,' admitted Smyth, a two-time winner this season. 'I'm looking for something to kick the back end of the year. This has certainly revitalized me.'
Hatalsky, a four-time runner-up in 2005, began his first round on the back nine and recorded six birdies on his front nine. He birdied the first to get to 7 under par, but an errant drive at the fourth knocked him down to minus-6.
He birdied the par-5 sixth and appeared to be in some trouble at the par-4 eighth. Hatalsky's approach came up short of the green and his chip stopped 8 feet from the cup. He drained that and parred nine to tie for the lead.
Mike Sullivan, Dave Barr, Danny Edwards and Gil Morgan are tied for eighth place at 5-under-par 67.
Defending champion Larry Nelson struggled to a 3-over 75 in Friday's opening round and is tied for 62nd place. Lee Trevino and Arnold Palmer both shot rounds of 6-over 78 and share 75th.