The American, a finalist at Flushing Meadows in 2017, has struggled with injuries this season but showed no sign of any lingering issues on Louis Armstrong Stadium court where she crushed 17 winners and broke her Czech opponent five times.

Nine-times Grand Slam women’s doubles champion Siniakova, who won the mixed doubles gold medal at the Paris Games earlier this month, struggled with her serve. She made just 52% of her first serves and produced 11 double faults.

After a competitive opening set in the first meeting of the two veteran players, the 14th-seeded Keys turned up the aggression to break to start the second.

Keys did not let up from there, slapping an inside out forehand winner to hold serve at love for 5-1 and rifling a service return Siniakova could not handle on match point to end the affair.

Keys reached the tournament’s semifinals last year where she faced Aryna Sabalenka and appeared to be rolling after winning the first set 6-0 but eventually lost in a heart-breaker.

This season she was forced to retire in the third sets from her matches at Wimbledon in July and Toronto earlier this month with injuries.

Next up for Keys in is a second-round meeting with Australian qualifier Maya Joint.