New York, February 16: Dominic Thiem was tested before reaching the Argentina Open semi-finals, while John Isner cruised through in New York.
A two-time champion in Buenos Aires, Thiem overcame Pablo Cuevas 4-6 6-4 6-3 in their quarter-final on Friday.
The top seed improved to 11-0 at the ATP 250 event, where Diego Schwartzman awaits in the last four.
The fourth-seeded Schwartzman was too good for Albert Ramos-Vinolas in a 6-1 7-5 victory.
The other semi-final will see Italian third seed Marco Cecchinato meet Guido Pella.
Cecchinato got past Roberto Carballes Baena 7-6 (7-3) 6-4, while Pella saved four match points in a 6-7 (3-7) 7-6 (11-9) 6-1 win over Jaume Munar.
At the New York Open, Isner served 16 aces in a 6-4 6-1 win over Australian seventh seed Jordan Thompson.
He will face fellow big-serving American Reilly Opelka in the semi-finals after the 21-year-old beat Guillermo Garcia-Lopez 6-3 6-4.
Last year's runner-up Sam Querrey overcame Jason Jung 6-3 3-6 6-3 and next meets Canadian qualifier Brayden Schnur, who edged Paolo Lorenzi 6-7 (7-9) 7-6 (7-5) 7-5.
Find the best IPL odds at 10Cric! Bet on all matches directly from your mobile phone.
Play casino in India at 7Jackpots, and enjoy real money games with fast and secure withdrawal options.