Narrative:

We called ZZZ ground control from the alley for taxi. We were cleared to 'taxi to xxl via C; left; north route. As we approached taxiway C-10; westbound on B; a B737 made a left turn immediately in front of us at C-10 from taxiway B. If we had not stopped as quickly as we did; there would have been a collision. We literally had to jam on the brakes. We made a radio call to ground that 'apparently airline X is waiting for airline Y to pass in front of us.' an unknown voice (not ground) said 'yeah; you better.' I have never seen such unprofessional and dangerous behavior from a professional pilot. It is not ok to turn in front of a moving airplane (us); even if they had been cleared to the gate (which we didn't hear because it happened before we were on the frequency. Ground control apologized; but the airline Y pilot is the one who nearly caused a collision. Ground didn't tell either of us to pass behind the other; but that doesn't make right to cut in front of another aircraft.whatever you do to a pilot who cuts in front of another airplane. Unsafe and unprofessional. Period.

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Original NASA ASRS Text

Title: Air carrier flight crew reported that another aircraft turned in front of them on the ramp and caused a critical ground conflict.

Narrative: We called ZZZ Ground Control from the alley for taxi. We were cleared to 'taxi to XXL via C; L; North Route. As we approached Taxiway C-10; westbound on B; a B737 made a left turn immediately in front of us at C-10 from Taxiway B. If we had not stopped as quickly as we did; there would have been a collision. We literally had to jam on the brakes. We made a radio call to Ground that 'apparently Airline X is waiting for Airline Y to pass in front of us.' An unknown voice (not ground) said 'yeah; you better.' I have never seen such unprofessional and dangerous behavior from a professional pilot. It is NOT OK to turn in front of a moving airplane (us); even if they had been cleared to the gate (which we didn't hear because it happened before we were on the frequency. Ground control apologized; but the Airline Y pilot is the one who nearly caused a collision. Ground didn't tell either of us to pass behind the other; but that doesn't make right to cut in front of another aircraft.Whatever you do to a pilot who cuts in front of another airplane. Unsafe and unprofessional. Period.

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.