I agree with eco (above). Pirri won the job out of training camp and Hrivik just doesn't have enough offensive upside to justify keeping him over Pirri.
With Nash, Zibs and Buch back, Pirri's offensive "upside" is nothing but a luxury. The only thing Pirri does better than Hrivik is shoot, and on a deep offensive team I don't know if that warrants a spot in the lineup.