Evgeni Malkin's fiancee, Anna Kasterova, gave birth to the couple's son in Pittsburgh at 11:45 a.m. ET on Tuesday, according to Russian newspaper Sovetsky Sport (sovsport.ru).
"Malkin and Kasterova welcomed birth of son," Sovetsky Sport tweeted. "CONGRATULATIONS."
The Penguins forward and Kasterova also applied for a marriage license in Pittsburgh on Friday, Pittsburgh radio station KDKA reported.
Malkin has 15 points in 18 Stanley Cup Playoff games and was plus-1 in Pittsburgh's 3-2 win in Game 1 of the Stanley Cup Final against the San Jose Sharks on Monday.
Game 2 of the best-of-7 series is at Consol Energy Center in Pittsburgh on Wednesday (8 p.m. ET; NBCSN, CBC, TVA Sports).