AT&T Byron Nelson 2017: James Hahn, Ricky Barnes Tied for Lead After Round 1

James Hahn and Ricky Barnes sit atop the leaderboard at the AT&T Byron Nelson in Irving, Texas, after they shot dueling 64s to card first-round scores of six under on Thursday afternoon.

However, Hahn and Barnes don't have much breathing room with Matt Kuchar, Jhonattan Vegas and Jason Kokrak among those sitting two shots back at four under. 

Here's an overview of the top of the leaderboard with 18 holes in the books at TPC Four Seasons Las Colinas: 

Hahn and Barnes were both in fine form during Thursday's first round, with the former carding six birdies and no bogeys on a blemish-free day.

Barnes, meanwhile, poured in eight birdies—including five on the front nine. In fact, Barnes was so locked in at one point that he carded four birdies in five holes during a stretch that spanned Nos. 6-10. 

And even though he dropped a shot on Nos. 2 and 15, Barnes was still able to secure his best round in more than a year, according to PGATour.com's Mike McAllister: 

The other big story of the day was Jordan Spieth, who made an equipment change after he missed the cut at the Players Championship last weekend. 

According to PGATour.com's Jonathan Wall, Spieth made the switch to a Scotty Cameron T5W Tour mallet putter to try and help with alignment issues. 

"It’s nothing crazy new," Spieth said, per Wall. "Obviously I’ve got a putter I’ve worn out for a number of years. It helps me line up a bit better, this one right now. That’s kinda been my struggle is lining the putter up where I want to. So I’m falling into a nice line and a nice setup, which has left me more comfortable."

For one round, at least, that decision paid dividends. 

Spieth shot a solid two-under 68 with the new putter, and he poured in back-to-back birdies on Nos. 7 and 8 to move into red figures after he played the back nine even following a start at hole No. 10. 

The PGA Tour's official Twitter account relayed highlights of Spieth's polished putting: 

One other performance of note was that of Jason Day—who is still looking for his first top-10 finish since February's AT&T Pebble Beach Pro-Am. 

Although Day's opening round was largely defined by inconsistencies, his composure in the face of adversity allowed him to enter the clubhouse tied with Spieth at two under. 

Case in point: While Day carded two bogeys over his first six holes, he funneled home a clutch eagle putt at the par-five seventh to regain his footing: 

Then there was Day's birdie at the 11th, which he managed to churn out despite landing his drive on the cart path, as Golf Channel documented on Twitter: 

As the leaderboard indicates, Day still has plenty of ground to make up if he wants to climb into contention.

But if he can polish his driving accuracy a bit and get in position for easier birdies on Friday after draining several long-distance efforts during Round 1, he could be poised to make some noise over the weekend.