The tech-infused league, founded by Tiger Woods and Rory McIlroy's TMRW Sports, features PGA Tour stars in team matches combining virtual and real-life play.
Atlanta Drive GC, last year's SoFi Cup champions, built a 3-1 lead after the opening nine-hole alternate-shot session and extended it in the singles before New York fought back.
Cameron Young and Matt Fitzpatrick won key points to tie the contest heading to the final hole, where Horschel holed a 37-foot eagle to seal victory.
Justin Thomas was sidelined for Atlanta Drive GC, joined by Patrick Cantlay and Lucas Glover, with Corey Conners and Chris Gotterup stepping in alongside Horschel.
After early holes were tight, Atlanta pulled ahead with Gotterup and Horschel winning crucial points, while New York's late rally left the match balanced until Horschel's finishing eagle ended the contest.
Jordan Spieth, Akshay Bhatia, and Billy Horschel were confirmed on Wednesday as the final three additions to the 20-player lineup for this year’s Hero World Challenge in the Bahamas.
Tiger Woods has confirmed that he plans to attend "every match" of his Jupiter Golf Links team's TGL campaign, even as he continues to recover from his most recent back surgery.
Tiger Woods is set to return to competitive golf, much to the delight of fans, as TGL - the technology-driven golf league he co-founded with Rory McIlroy - unveiled its schedule and teams for the upcoming season on Monday.
Atlanta Drive won the inaugural TGL title when they came back from the dead for a 4-3 victory over New York on Tuesday night.
