B737 Next Generation Undifferentiated
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 177; Flight Crew Type 2301
Situational Awareness
ATC Issue All Types; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Human Factors; Procedure
Descending into Denver we were cleared to descend via the ANCHR4 Arrival and told to expect the RNAV Zulu RWY 35R. We loaded that approach into the FMS and sequenced the FMC from DOGGG way point. Just prior to the turn at FULLA the controller changed the approach to a Visual RWY 35R; so we loaded the FMC with the ILS 35R for back up guidance. The controller gave that clearance to expect the Visual about 6 miles from FULLA - which is the last point prior to a southbound 173 turn. In reprogramming the approach we did not get the FMC programmed in time for the FMC to make that turn. We immediately noticed the airplane not turning so I disconnected the auto pilot and made the southbound turn to 173 while leveling off at 11;000'. In the turn the controller asked if we were turning and replied that we were. The First Officer was still programing the FMC with the correct RWY while in the turn so we asked for a vector and the controller gave us a 170 heading. We don't think we deviated more than 1/8 to 1/4 mile from the arrival path. FMC reprogram completed just prior to DOGGG and Visual Approach complete without incident.
B737NG Captain reported a track deviation occurred on arrival into DEN following a late runway change.