Commercial Fixed Wing
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 17
Distraction; Confusion; Communication Breakdown; Situational Awareness
ATC Issue All Types; Airspace Violation All Types; Deviation / Discrepancy - Procedural Other / Unknown
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance
ATC Equipment / Nav Facility / Buildings; Human Factors; Procedure
While working Sector X during weather and re-routes; the adjacent sector (Sector Y) to the southeast of me was overly saturated with aircraft in a complex sector with hot restricted airspace.  The R-side at Sector Y asked for a D-side but was not provided due to staffing.  I was assisting R-Y from my position.  A non-radar aircraft from Mexican airspace was not coordinated by Mazatlan Center and did not get tracked up.  The aircraft flew through Sector Y and my Sector [X] to the northwest undetected until the adjacent sector to the northwest alerted me of Aircraft X's limited data block.  I quickly got the aircraft on my frequency; radar contacted the aircraft and handed him off to the next sector.This has been an on-going issue with non-radar aircraft from south of the boarder.  Better coordination and tracking procedures need to be established.
ZLA Controller reported an airspace deviation when an air carrier went through two sectors undetected; until the third sector Controller identified the aircraft.