Alexander Zverev is 22, Dominic Thiem is 26, and one of them will get the chance to appear in the Australian Open final for the first time. Their semifinal is under the lights at night in the only singles match of Day 12 at Melbourne Park.
It's a matchup between two of the 20-somethings that folks have been expecting to break through the Grand Slam dominance of the Big Three: Rafael Nadal, Novak Djokovic and Roger Federer combined to win the past 12 major championships in a row.
While this is the first time in a major semifinal for the No. 7-seeded Zverev, it is the fifth for No. 5 Thiem, whose previous four all came at the French Open, where he lost in the past two finals to Nadal.
Thiem eliminated 19-time major champion Nadal in a thriller in the quarterfinals Wednesday; Zverev got past three-time major champion Stan Wawrinka.
Very hot. Chance of a late storm. High of 109 degrees (43 Celsius).
Hot. High of 102 degrees (39 Celsius).
THURSDAY'S SINGLES SEMIFINALS
Men: No. 2 Novak Djokovic beat No. 3 Roger Federer 7-6 (1), 6-4, 6-3.
Women: No. 14 Sofia Kenin beat No. 1 Ash Barty 7-6 (6), 7-5; Garbiñe Muguruza beat No. 4 Simona Halep 7-6 (8), 7-5.
Men: No. 2 Novak Djokovic vs. No. 3 Roger Federer at night
STAT OF THE DAY
18 — Number of years since an American woman beat the No. 1 player at a Grand Slam tournament -- Serena Williams beat her sister Venus at Wimbledon in 2002 -- until Kenin's victory over Barty.
QUOTE OF THE DAY
"I know people haven't really paid attention much to me in the past. I had to establish myself, and I have." — Kenin.