"Unbeaten record" means that someone or something has never been defeated or lost in a competition or situation. It refers to a performance or accomplishment where there have been no losses or defeats. Full definition
And they have participated into the record of Real Sociedad which is the highest number of unbeaten record in the competition. (sportseon.com)
Ernesto Valverde defended his Barcelona side's Champions League exit as they push for the La Liga unbeaten record against Valencia. (skysports.com)
The fact that Sissoko also has raw pace and strength to fall back in makes him doubly dangerous, however — and is why he was the best player on the pitch as Newcastle finally ended Chelsea's long unbeaten record at Stamford Bridge yesterday. (caughtoffside.com)