As an extension of H.264/AVC, Scalable Video Coding (SVC) provides the ability to adapt to heterogeneous requirements. However, transcoding between SVC and AVC becomes necessary due to the existence of legacy AVC-based systems. The straightforward full re-encoding method requires great computational cost, and fast SVC-to-AVC spatial transcoding techniques have not been thoroughly investigated yet. This paper proposes a low-complexity SVC-to-AVC spatial transcoder in hybrid domain (pixel domain & transform domain) with drift compensation. In the pixel-domain transcoding, a fast re-encoding method is proposed based on mode mapping and MV refinement. In the transform-domain transcoding, the quantized transform coefficients together with motion data are reused directly to avoid re-quantization loss. At last, the drift problem in proposed transcoder is solved. Simulation results show that proposed transcoder achieves averagely 96.4% time reduction compared with the full re-encoding method, and outperforms the reference methods in coding efficiency.