Juan Martín del Potro defeated the defending champion Roger Federer in the final, 6–4, 6–7(8–10), 7–6(7–2) to win the men's singles tennis title at the 2018 Indian Wells Masters. He saved three championship points en route to his maiden ATP Tour Masters 1000 title, following three previous runner-up finishes. Federer and Rafael Nadal (despite having withdrawn from the event) were in contention for the ATP No. 1 singles ranking. Federer retained the top ranking by reaching the semifinals.