Radwanska, the defending champion and seeded first this year, was declared a winner Friday when Camille Pin retired in the second set. Radwanska was ahead 6-2, 1-0 when Pin was unable to continue.
Dushevina, unseeded this week, advanced on a 6-3, 6-3 decision over Iveta Benesova in the quarterfinals of the hard-court tournament.
Friday's other quarterfinals saw fourth-seeded Carolina Wozniacki breeze by fifth-seeded Anabel Medina Garrigues 6-1, 6-3; and No. 3-seeded Katarina Srebotnik post an easy 6-2, 6-0 win over Ruano Pascual.
Saturday's semifinal pairings could have Radwanska and Dushevina in the finals again as Wozniacki faces Radwanska and Srebotnik meets Dushevina. Radwanska won the only career meeting with Wozniacki in straight sets also on a hard court. Srebotnik has won two of the three times she has played Dushevina.
Swim Week Miami Beach 2014 [PHOTOS]