( CNN ) -- It 's a big dilemma : Be with your wife for the birth of your first child , or stay at work with the hope of an $ 11 million payday . For golfer Billy Horschel , it 's a no-brainer . `` There was n't much discussion . I brought up the question , she said : 'You 're staying . ' `` Horschel is one of five players who can claim the $ 10 million jackpot for topping the PGA Tour 's FedEx Cup playoff series by winning the $ 1.44 million Tour Championship finale in Atlanta . The 27-year-old made the best possible start Thursday as he tied for the first-round lead with longtime friend Chris Kirk , who heads the FedEx standings from second-placed Horschel . Horschel won last week 's BMW Championship and was joint runner-up in the second of the four playoff events , so his hopes are high that he can secure his family 's financial future this weekend . `` My wife is totally on board , '' he told the PGA Tour website after his four-under-par 66 . `` She 's a golfer . She understands what it all means . I 've probably got the greatest wife out here . '' Their daughter , to be named Skylar Lillian , is due on September 27 but could arrive earlier . Horschel said if his wife Brittany does go into labor in the next few days , he does n't want to be told until he completes his round . Then , with a private jet standing by , he will make the one-hour flight back to Florida . Because of the tournament 's restricted 29-man field -- there would usually be around 150 players for the first two rounds of a regular PGA Tour event before the halfway cut -- he will have time to get back to resume playing the next day . `` I wo n't find out on the course , because my focus may be taken away from the task at hand , '' Horschel said . `` But after the round 's over with , I will be flying home , spend a few hours and then flying back later that day or the next morning before the round of golf . `` Having a chance to win $ 10 million and our first child on the way -- it 's pretty amazing . '' Last year , Hunter Mahan -- who carded 74 Thursday to be well off the pace -- withdrew from the Canadian Open while he was leading to be at the birth of his first child . `` Hunter did a great thing last year pulling out , '' Horschel said . `` But I would think if he was in my position with winning , having a chance to win , roughly $ 10 million more , if you had the Tour Championship winner 's check and everything , I think it would be maybe a no-brainer to stay put and keep playing and go home in between rounds . '' Impending fatherhood is only adding to the excitement for Horschel , who partnered the comparatively calm Kirk in the final group to go out Thursday . They have known each other since playing at rival schools and progressing through the amateur ranks . `` He looks like he 's a Fred Couples walking slow and nothing affects him , '' Horschel says of the 29-year-old Georgia native . `` And I think I walk slow , but as I 've seen on the coverage last week , it looks like I 'm sprinting around the greens and the golf course ... The emotional level is a little bit different . '' They were one shot clear of another four players tied for third : Masters champion Bubba Watson , fellow Americans Jim Furyk and Patrick Reed , plus Australian Jason Day . World No . 1 Rory McIlroy -- who like Kirk , Horschel , Watson and Mahan can secure the bumper jackpot with victory Sunday no matter where any other player finishes -- was tied for 11th on 69 with Adam Scott , Sergio Garcia and Ryan Palmer . If none of the top five win , then the permutations get complicated , but it 's possible for any player in the entire field to claim the $ 10 million with victory .
Billy Casper shares lead with Chris Thompson after round one of Tour Championship . Horschel 's wife is due to give birth to their first child this month . He is in contention to win the $ 1 million FedEx Cup prize . He says he will keep playing if his wife goes into labor during tournament .