Penrith were dealt a blow on the eve of their semi-final clash with powerhouse winger Brian To'o ruled out of the clash against the Eels.
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The Origin flanker suffered a "minor ankle complaint", according to the club, with his place on the wing taken by Brent Naden.
Eels coach Brad Arthur has confirmed Ryan Matterson will return in Saturday’s semi-final against the Panthers.
Matterson was overlooked by Arthur for last week’s elimination final against the Knights after serving a three-match suspension for a high tackle on Manly’s Brad Parker in round 22.
Arthur has since had a change of heart and will use Matterson in a different role against Penrith.
"At some stage Matto will be put into the game," Arthur said. "It’ll probably more so in the middle to give us some fresh legs in the middle."
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Matterson has played 16 matches for the Eels this season, starting each in the second row.
Panthers coach Ivan Cleary said on Friday that his injured trio, fullback Dylan Edwards, prop Moses Leota and bench forward Scott Sorensen (wrist) would be good to go.
Late Mail: Finals week two
Panthers v Eels, Saturday 7.50pm at BB Print Stadium, Mackay
Panthers: Brian To'o is out of the Panthers side with a minor ankle injury. Brent Naden has been named to start on the wing. In a game day change Liam Martin has been promoted to the starting side with Viliame Kikau going to the bench.
Front-rower Moses Leota (leg), fullback Dylan Edwards (foot) and interchange forward Scott Sorensen (wrist) were declared certain starters by coach Ivan Cleary on Thursday.
To'o and Tyrone May were the two players left out 24 hours before the match. Spencer Leniu was the last man cut an hour before kick-off and Izack Tago is the 18th man.
The Panthers have won six of their past eight games against the Eels.
Eels: The Eels are 1-17 with no late changes.
Nathan Brown (leg cork) is expected to play despite failing to finish last week's clash against Newcastle.
Clint Gutherson and Blake Ferguson were also hampered by leg injuries against the Knights but are in no doubt this week.
Ryan Matterson is back on deck after being left out of the 17 last week. Makahesi Makatoa drops to the reserves to make way for Matterson.
Oregon Kaufusi and Jake Arthur were omitted 24 hours before kick-off. Tom Opacic was the last man cut from the squad an hour before kick-off and Makatoa is 18th man.
The Eels have not won back-to-back finals games since 2009.
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