Narrative:

Flying FMS bridge visual runway 28R. At approximately 1;500 to 1;200 feet AGL; sfo tower cleared aircraft Y to cross runway 28R. At either taxiway U or right. Couldn't tell which one exactly. I looked over to the first officer and asked him did he just clear that guy to cross the runway? Immediately sfo tower told aircraft Y to hold position. No answer. Tower then said aircraft Y stop. No answer. I told first officer to prepare for a go around. After a 3rd call from tower; aircraft Y was now in the middle of the runway. Tower then directed the go around. The FMS bridge visual has a specific go around procedure listed. Runway heading to 3;000 ft. That's not what the go around instructions given from tower which was an added distraction. Next approach was uneventful.

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Original NASA ASRS Text

Title: B737 Captain reported that a communication breakdown between ATC and another aircraft resulted in a runway incursion and a go-around.

Narrative: Flying FMS Bridge Visual Runway 28R. At approximately 1;500 to 1;200 feet AGL; SFO Tower cleared Aircraft Y to cross Runway 28R. At either Taxiway U or R. Couldn't tell which one exactly. I looked over to the First Officer and asked him did he just clear that guy to cross the runway? Immediately SFO Tower told Aircraft Y to hold position. No answer. Tower then said Aircraft Y stop. No answer. I told First Officer to prepare for a go around. After a 3rd call from Tower; Aircraft Y was now in the middle of the runway. Tower then directed the go around. The FMS bridge visual has a specific go around procedure listed. Runway heading to 3;000 ft. That's not what the go around instructions given from Tower which was an added distraction. Next approach was uneventful.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.