The Bisons will now head home for an eight-game homestand that starts Tuesday with the first of four game-series against the top team in the International League, the Durham Bulls.
The PawSox used power and patience to earn the victory the Bisons. Frandsen's homer with one out in the first got them on the board and back-to-back walks to Mark Wagner and Dusty Brown by Herd starter Bobby Livingston later in the inning gave Pawtucket a 2-0.
Wagner and Nava drew walks around a Brown double in the fourth inning to load the bases again against Livingston. Sac flies from Matt Sheely and Josh Reddick pushed the PawSox lead to 4-1.
Nava's homer off reliever Travis Blackley in the sixth sealed Pawtucket's second win over the Bisons in six games this season.
Buffalo scored their lone run in the bottom of the second. Chris Carter led off with the single and got himself to third on a Pawtucket error and a groundout. Andy Green scored his teammate from third with a groundout to the right side.
The loss for Buffalo went to Livingston (0-2). He allowed four runs on five hits and five walks in five innings of work.
BISONS NOTES:Mike Cervenak singled in four trips to extend his hit streak to a Bisons' season-high 11 games...Mike O'Connor pitched a scoreless ninth inning. He has made five consecutive relief appearances without allowing an earned run...The Bisons are no 6-6 on the road this season.