Linearization of massive MIMO arrays is a significant computational challenge that typically scales with the number of antennas. In this work, we introduce a beam-oriented digital predistortion (DPD) scheme for OFDM-based massive MIMO systems that applies predistortion before the precoder in the OFDM guard-band subcarriers. Using simulation results, we show that, for a 64 antenna massive MIMO array, our proposed method can achieve the same DPD performance as a conventional DPD method while requiring an order of magnitude fewer multiplications.