From Longman Dictionary of Contemporary Englishone to watchone to watchsomeone or something that people should pay attention to because they are interesting or exciting In the tournament so far, Italy’s Stefania Croce looks like the one to watch. → watch
Examples from the Corpus
one to watch• Her association with Feist has moved sales of her own books up several notches, and this will one to watch.• Rab figured him the one to watch.• Shiatsu massage is the current one to watch for.• The one to watch would be tomorrow morning's debate on the Government's immigration policy. 