Noah Goodwin outlasted John Pak with a conceded eagle on the 20th hole Friday to advance to the U.S. Junior Amateur championship match.
The 16-year-old Goodwin, from Corinth, Texas, will face Australia's Min Woo Lee in the 36-hole final Saturday at The Honors Course.
Goodwin and Pak, from Scotch Plains, New Jersey, matched pars on 17, bogeys on 18 and pars on 19 before Goodwin won on the 20th.
The 17-year-old Lee held off Eugene Hong of Sanford, Florida, 1 up with a par on the 18th. Lee's older sister, Minjee Lee, won the 2012 U.S. Girls' Junior and has two LPGA Tour victories.
In the morning quarterfinals, Goodwin beat Australia's Fred Lee 5 and 4, and Min Woo Lee topped Brandon Gillis of Nashua, New Hampshire, 4 and 2.