Nadal cemented his return from a seven-month injury layoff with his first hardcourt title since 2010.
He came back in February to post a runner-up finish in Vina del Mar, followed by victories at Sao Paulo and Acapulco.
But none of those modest claycourt tournaments posed the challenge he faced at Indian Wells, where the field featured 49 of the top 50 players in the world.