Juan Martín del Potro defeated Damir Dzumhur 6–3, 7–6 in the semi-final of the ATP 250 Los Cabos tournament on hard court on 3 August 2018, confirming his status as the strong pre-match favourite with odds of 1.15 against Dzumhur's 6.52. Del Potro controlled the opening set convincingly before the second set proved more competitive, requiring a tie-break to secure victory. The Argentine's win extended his form in the tournament and positioned him for the final.