Froome, eyeing his fourth Tour de France title, finished seventh in Saturday’s stage, one second behind Matthews. Aru was 30th, 26 seconds behind Matthews.
Froome came into the day six seconds behind Aru after ceding the lead to the Italian on Thursday. Now, he leads by 19 seconds over Aru with seven stages remaining.
The top four in the overall standings are separated by 29 seconds. It has turned into the tightest yellow jersey battle in Tour history.
Sunday’s Stage 15 is 118 miles with four categorized climbs, but none of the most difficult variety.
NBC Sports Gold coverage starts 6:55 a.m. ET, with NBCSN coming on air at 7.