Caroline McTaggart won twice at the Speedo Junior National Championships in San Antonio, Texas.
Three current Bruins, one future Bruin and a UCLA alum are in competition in Russia and Oregon.
Polyakova also finishes sixth in the 3-Meter Mixed Synchro.
Seven of the 15 Bruin participants at the L.A. Invitational reached championship finals.
Next up for the reigning U.S. 1500 Free champ are the FINA World Championships in August in Russia.