Bam Fadahunsi scored after five minutes before Joe Munro and Ellis went over, Paolo Odugwu getting a try for the visitors.
But Jack Moorhouse’s second-half score put Sale on the way to a bonus point, secured late on by Johnny Leota and Odugwu.
Park were almost ahead in 20 seconds as Fadahunsi picked up Emiliano Calle Rivas’ kick-off but was denied by Odugwu.
The winger got his reward four minutes later, finishing a slick move from Park’s scrum.
But Sale were back on level terms within minutes, the Spanish international threading a kick to Odugwu.
Bam Fadahushi scores Park's first try
It was all Park then as Joe Munro finished a maul on 17 minutes before Hugo Ellis got his third try in three games with a déjà vu move five minutes later.
Sale’s afternoon got worse a minute later as scrumhalf Matt Bradley was sin-binned for intercepting Jack Gash’s breakaway.
Park responded immediately, Ellis repeating his efforts move-by-move for the bonus point.
But it was the visitors who came out firing in the second half, Moorhouse scoring after a driving move.
Odugwu and Ed O’Keefe had chances to score after 50 minutes but the ball did not bounce for them.
Park secured victory with a penalty kick five minutes from time, Oli Grove finding the mark from 10 metres.
But the visitor’s reward came on 80 minutes as Leota finished a maul and Odugwu scored from a full-length pitch run, earning the bonus point.
Park are going back to university as they face Loughborough Students on February 16 at Ashby Road.
The home side are having a difficult season, which only got worse in a 47-30 loss to Darlington Mowden Park at the Northern Echo Arena.
Park will hope for a repeat of their last encounter, which saw a 39-31 win at the Rock in October.
Rosslyn Park
Tries: Fadahunsi 5, Munro 17, Ellis 22, 27
Conversions: Lound 6, 18, 23, 28
Penalties: Grove 75
Team (15-9/1-8): Russell Weir; Bam Fadahunsi, Oli Grove, Joe Munro, Charlie Amesbury; Greg Lound (Henry Robinson 55), Jack Gash; Ali Wade (Paul Doran-Jones 48), Karl Gibson (Hughes 57), Stewart Maguire (Nick Lovell 48, Wade 72); Adam Frampton, Gregor Gillanders; Henry Spencer, Arthur Ellis, Hugo Ellis © (Hugh Tizard 39)
Attendance: 610
Referee: Daniel Collins
Warren Muggleton
Images: David Whittam
February 11, 2019