The 33-year-old, who is out of contract at the end of the season, took his tally to seven tries in his last five matches as the Challenge Cup finalists secured a fifth successive win in all competitions.
Watson said: “He was outstanding, we’re talking about him every week at the moment, aren’t we?”
Asked if he was keen to tie up Inu for 2021, Watson said: “I had a really good chat yesterday with his agent on my way into training.
“His agent is from Australia and, from what he says, Kris is just focusing on his football at the moment and everything will take care of itself.”
Inu, who also kicked four goals for a 20-point haul, almost single handedly brought the Giants’ three-match winning run to an end as caretaker coach Luke Robinson experienced defeat for the first time.
But the Red Devils had to do it the hard way once more, coming from behind for the third successive game to gain the spoils.
Watson added: “They are a hard-working group. They are gritty as a team and seeing us win late games is no surprise because they show that mentality in the way they train.
“It probably took the boys a few weeks to buy into the season but we’re getting the rewards on the back of it now.
“What we’re doing is sticking to the processes and it’s working for us.”
Salford went into their penultimate game before Wembley without five members of their semi-final team and they now need to negotiate a league fixture with Hull KR on Tuesday before they can fully concentrate on the big game.
Watson said: “I thought there were some players who really stood up today. They probably nailed their spots down.
“That helps you when you’re behind on the scoreboard and you know you are playing for a place Wembley. It probably brings a bit more out in them.”
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