The Waterford-born winger joined former-boss Keane this week in a double deal that included Sunderland flop David Healy.
The pair have joined on loan deals for the rest of the season and are expected to form a new-look strike partnership as Keane plots to overthrow his one-time Celtic boss Gordon Strachan.
Murphy insists that if he is allowed to play in his preferred attacking role, rather than on the left flank where he often featured in Sunderland colours, he will prove his marksmanship.
People look at my record and think I haven't scored many goals. But I've probably played 70 per cent of my Sunderland matches on the left of midfield. If I play up front, I feel confident I'll score goals,
The gaffer knows he'll get more out of me if he plays me as a striker, as he did at Sunderland.
Hopefully we can add a bit of quality to the team.
Murphy believes his partnership with Healy can transform Keane's troubled campaign.
I know what he's like and what he wants. He's one of the easiest managers you could play for. You know exactly what he wants and if you're not doing that he'll tell you.
He's honest about everything and I certainly enjoyed my time with him at Sunderland,
Healy who scored on his debuts for Leeds, Fulham, Sunderland and Northern Ireland is hoping to continue that run against Middlesbrough.
Fans love goalscorers and they love heroes. Hopefully the two of us can be the ones who score those goals, said Northern Ireland's 35-goal record scorer, who hasn't started for Sunderland this season.
It's been tough, he said.
The last thing you want is to train from Monday to Friday, then not play on the Saturday.
I've worked with Roy and I played with him at Manchester United.
We know each other and he's taken a chance by bringing both of us down here. We know what makes him tick and, more importantly, what doesn't make him tick.
He always takes a look at himself, to see where he's going wrong, before looking at others. He dragged Sunderland from the bottom of the Championship to become an established Premier League club.
Now he's come down here for the same challenge.