A method of operation in a high-speed Ethernet transceiver is disclosed. The method includes engaging in an autonegotiation process with a link partner transceiver to indicate whether one or more sub-rate modes of operation are supported. Each sub-rate mode of operation corresponds to a sub-data rate that is less than a maximum data rate. The autonegotiation process is terminated. The transceiver then participates in a training process. The training process includes receiving a first training sequence corresponding to a first sub-data rate that is less than the maximum data rate. A signal quality parameter for the received first training sequence is measured. The training sequence is terminated based on the measured signal quality parameter failing a predetermined criteria. A second training sequence is then initiated that corresponds to a second sub-data rate that is less than the first sub-data rate without starting a second autonegotiation process.