Ivan Rakitic came to Barcelona's rescue as the substitute fired Quique Setien's side to a 1-0 win over Athletic Bilbao.
All eyes were on Lionel Messi, chasing his 700th career goal, but he had to settle for an assist to Rakitic's 71st-minute strike that lifted Barcelona back above Real Madrid.
Amid Messi's pursuit of a slice of history, a drought had looked to be undermining Barcelona's LaLiga title bid until the late twist.
After a goalless draw at Sevilla on Friday, Barcelona were far from their best again.