Opposition view: McKellar salutes Tigers trio after win against Saints
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McKellar was full of praise for the impact man of the match Tommy Reffell had at the breakdown, while also saluting scrum-half Ben Youngs and fly-half Handrè Pollard.
Tigers secured a 26-17 win as tries from Francois van Wyk and Hanro Liebenberg made sure of a home victory at Mattioli Woods Welford Road.
And when asked what he felt was the secret behind the success, McKellar said: "(Stopping Northampton) started with our kicking game and our exits.
"(Ben) Youngs and Handrè Pollard were outstanding. They're world class players and our kick-chase and pressure in the air was outstanding.
"It put us in good areas of the field and if you back that up with defence and set-piece dominance, all of a sudden you're really squeezing and shaking the opposition.
"We did that, we managed to get some scoreboard pressure.
"We're disappointed to have that maul try (from Charlie Clare) disallowed but overall we're really pleased with how we went about it.
"We had to grind out a win and we did that."
Reffell was a menace at the breakdown, with the Wales flanker winning his side a succession of penalties.
And McKellar said: "You've got to defend well to give Tommy the opportunities that he had and it was good to have him back.
"With the game these days, you can't be defending for 20 or 30 phases so to have someone like Tommy to be able to force turnover on the ground off the back of what others do, just adds another string to our bow."
It was McKellar's first experience of an East Midlands derby.
And he said: "I'm obviously happy. It's a big derby game, the first one for myself, it's a special occasion and good for us to front up and get the win.
"Physically, we were outstanding. We had set-piece dominance and our defensive pressure in the first half in particular was what won us the game.
"It would have been nice to have scored one or two more, but overall we're really pleased."
Tigers had won just one of their five league matches going into the game against Saints.
And McKellar said: "You need to win. When you're one from five, we obviously weren't happy with that.
"I don't think it was must-win territory but when it's a Tigers-Saints derby game, you don't want to lose them no matter where you are in the table."