Parramatta coach Michael Hagan denied his side's finals chances had nosedived despite suffering a third straight NRL loss against an under-strength Manly.

The Eels, who desperately needed a win, failed to capitalise on a clear opportunity for an upset after Manly lost halfback Matt Orford (thigh) before the kick-off and then five-eighth Jamie Lyon (knee) and Jason King (ankle) early in the first half at Brookvale Oval on Friday night.

The signs looked good for Parramatta when they led 6-0 but they failed to stop the in-form Sea Eagles, who ran out convincing 28-10 winners.

The loss now leaves Parramatta in serious danger of losing touch with the top eight.

If Penrith beat the Gold Coast, it would leave Parramatta three points outside the top eight with only seven rounds remaining.

"We said [we needed to win] five from eight last week to make the finals and it's now five from seven, so the maths and the equation hasn't changed to much," Hagan said.

"I don't think we're too far away from sorting it out. But we know we've got seven pretty tough games to follow and we're going to have to win five of those to be thereabouts."

Hagan admitted the Eels let an opportunity slip.

"The game was there to be won but you can't be 70-80 per cent against Manly," Hagan said.

"You've got to be at your best and I thought without Orford and when Lyon went off we were a genuine hope."

The Eels are hoping to get their campaign back on track when they host the last-placed Cowboys at Parramatta Stadium on Friday night.