Russell rallied to upend Young 1-6, 6-1, 6-4 and advance on the grass courts at Newport, R.I. Harrison battled past Ruben Bemelmans 7-6 (10-8), 6-7 (5-7), 7-5 in 2 hours, 48 minutes at the International Tennis Hall of Fame.
Nicolas Mahut of France, the 2007 Newport runner-up, beat Swiss Marco Chiudinelli 6-0, 7-6 (7-2).
Other winners Monday included American wild card Jack Sock, Israeli Dudi Sela and two-time Hall of Fame runner-up Olivier Rochus of Belgium, who squeezed past Japan's Go Soeda 6-4, 3-6, 6-3.
Top-seeded American John Isner is seeking to defend his Hall of Fame title this week.
The tournament got under way following the weekend inductions of former world No. 1s Jennifer Capriati and Gustavo Kuerten, as well as former U.S. Open champ Manuel Orantes of Spain.
Notable deaths of 2014 [PHOTOS]