Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may determine candidate resources on one or more physical sidelink shared channels (PSSCHs) that are clear for transmitting at least two transport blocks, based at least in part on sensing a plurality of subchannels on the one or more PSSCHs with respect to listen-before-talk completion instants for the at least two transport blocks. The UE may select, from among the candidate resources, transmit resources on the one or more PSSCHs for transmitting the at least two transport blocks such that the at least two transport blocks are transmitted in one of: different subchannels of a same slot, or contiguous slots of a same subchannel. The UE may transmit the at least two transport blocks in the transmit resources. Numerous other aspects are provided.