Because this is a man who never shies away from a fight, in fact he actively encourages the opposition to bring it to him.
And this weekend, Harrison is desperate to be the one taking it to a powerhouse Sale Sharks side.
Saints are well aware what lies in wait when they head north - they have been there, done it and worn the bruises.
Sale will look to overwhelm a Saints team who struggled to deal with Leicester’s physicality during a chastening 55-26 defeat at cinch Stadium at Franklin’s Gardens last Saturday.
And Harrison and Co are well aware of how much they will need to step up their power play if they are to stand any chance of sinking the Sharks.
“They’re a team that look to bully you, and the best way to face bullies is to take the fight to them,” Harrison said.
““We can do it.
"We saw how we played at Exeter and how we played against Sale last season - we went out and bullied them and came away with the result.
“We’ve just got to, for the lack of a better term, pick our nuts up and go and get them.”
Saints have lost on each of their past four visits to the AJ Bell Stadium and, overall, they have a terrible record there.
The black, green and gold have won just four of the 12 matches they have played against Sale at the AJ Bell Stadium.
And Harrison, who made his Saints debut in 2012, the same year the AJ Bell Stadium hosted its first game, said: “Saints don’t have a good record up there and it’s an exciting challenge.
“It’s where you see what we’re all made of.
“We’re really looking forward to it and it’s a chance to go and put things right.
“It’s time to go take a scalp up there.
“They’re a really good team, it will be a hard challenge but we’re looking forward to it.”
Saints will have to make the trip to Sale with something of a skeleton squad as it has been thinned out by several international call-ups and injuries.
But Harrison is delighted for those who will represent their country this autumn and he insists Saints should be able to deal with the absences.
“You’re really happy for players who get called up to play for their countries,” Harrison said.
“You play rugby to play at international level and go on to higher honours so it’s cool to see them go away, but it’s a little bit nervewracking seeing how thin the squad’s got.
“It’s not been a gradual thing - everyone’s gone away all at once.
“We should be alright but it’s a bit nervewracking seeing boys going into the physio room and getting treatment - it’s like ‘I hope he’s alright’, but we should be all good.”
Saints were hindered by the loss of players last weekend, having to start centre Rory Hutchinson at full-back for only the second time in his first-team career.
Tommy Freeman, who is back this week, and George Furbank were away with England, while Ahsee Tuala is injured.
And Saints’ overall showing against Leicester was far from what it needed to be as the Tigers triumphed in enemy territory, racking up their biggest ever score in a derby-day clash at the Gardens.
“It was extremely frustrating,” Harrison said.
“I feel like in the second half we got our game back together and started putting it on them, but it was just unfortunate that we let so many opportunities slip in that first half.
“We didn’t play our game until the final five or 10 minutes of the first half and we came away with a try there.
“It was extremely frustrating and disappointing really.
“When you look at how many points we missed out on top four by - it was 14 - we’ve thrown two games away this season that could count against us in the back end of the season.
“It’s frustrating but you’ve got to take your lessons and take that into Sale.”
One thing Saints know they must do better is remain calm under pressure.
They made far too many errors and gave away far too many penalties against Tigers.
And Harrison said: “We try as hard as we can in training to replicate that pressure so you almost go back to your basics, your core fundamentals and stick to your game plan.
“I feel we went away from that at the weekend, we weren’t playing wide like we like to and we went into our shells a little bit.
“We’ve been trying to simulate it in training and make sure when we do get under pressure we go back to what we’re good at and what we know so that we play the Saints way.
“It’s just trying to find that balance and we showed at Exeter that we can do it.
“Our leaders, myself included, probably needed to step up a little bit more and calm everything down.
“It’s a lesson learned and a valuable one for us that we’ll take on this week and moving forward for the whole season.”