Jermaine Longmire, 42, has not been charged in the June 24 sexual assault of the woman in the park, but the sources said DNA links him to the incident.
The Central Park sexual assault prompted a manhunt for the suspect, who police say attacked the sunbather in the Great Hill section of the park near 104th Street in the middle of the afternoon.
Longmire has been in custody at Rikers Island after he was charged with groping a 27-year-old woman on a southbound A train platform on the Upper West Side on June 15.
In that case, Longmire is accused of coming up behind the victim and putting his hand under her dress.
Police say he has five previous arrests in New York City, as well as prior arrests in Florida, including for sex crimes.
No charges have been filed against him in the Central Park case, which is expected to go before a grand jury.