And with the likes of Brian O'Driscoll, Gordan D'Arcy and Shane Horgan likely to feature in Leinster blue as the opposition, Best is adamant that any international camaraderie will be pushed to one side.
"It will be the same as any other match for me. The interprovincial matches are always highly competitive so you can't let things like that (being Irish team-mates) effect you because once you get out there with a white jersey on, you have to be a professional."
The 28-year-old last donned the Ulster jersey back in May when the province closed their 2006/07 season with a 16-10 win over Edinburgh in Belfast. In the weeks that followed Best was named as one of eight Ulster players selected to tour Argentina with the Ireland squad.
Other than a couple of weeks back in Belfast - one of which was spent with the Ireland panel in preparation for the Ravenhill World Cup warm-up match against Italy in August - he has been on Ireland duty almost the whole time.
Now, almost two months after the Italy game and after a frustrating World Cup (where he gained four caps but got just 44 minutes of game-time in the green shirt), Best is back home and keen to get back to business with Ulster.
His first task will be to help Mark McCall's charges climb their way back up the Magners League table after three successive defeats.
"It's been a while since I've played with the Ulster boys so it's great to have the chance to reintegrate into the squad before we have a match. Now we're really getting stuck into training so that we can gel again before playing Leinster on Friday week," he admitted.
Despite Ulster's recent poor form, Best believes that they can still topple a full strength Leinster team next week.
"I think the structure of our defence will have to be at its best to fend off Leinster's back-line. It's important for our forwards to be winning the set pieces and performing at the breakdown, because it's a derby match the intensity is always high so we'll be giving it everything we've got."