There are certain fixtures you look at and underline with red pen as potentially season-defining ones and it's time to get that felt tip out of your pencil case.
Premiership leaders Ballymena United take their 19-match unbeaten run to champions Crusaders today in a mouth-watering clash that could have huge ramifications in the race for the Gibson Cup.
After what has been, for their high standards, a topsy-turvy start to the campaign, the Crues have started to look more like their old selves, with four league wins on the bounce that have taken them above Glenavon into third spot in the table.
They still trail the surprise pace-setters by five points, with Linfield sandwiched in between ready to pounce on any slip by the Braidmen, who currently lead the Blues by two.
It will be the sides' fourth meeting of the campaign and it has been advantage Sky Blues thus far, the pair playing out a brilliant 2-2 draw at Seaview at the start of the season before Crusaders were handed a 3-0 thumping at the Showgrounds.
Their last meeting came at today's venue when Ballymena squeezed through by the only goal of the game in the League Cup semi-final, but David Jeffrey knows that whatever has gone in the past is simply history.
"Crusaders on Boxing gave a thumping to Cliftonville and were quite magnificent from the reports that have come through to us," he said.
"And then at Glentoran, where Glentoran were coming off the back of a difficult Boxing Day wanting to evidence to people that they are worthy of wearing the red, green and black.
"They gave absolutely everything and yet Crusaders came back and got a goal a right at the death. We know Tuesday is going to be very tough, we have a number of players who will not be available."
With games coming thick and fast, injuries are taking their toll on Ballymena.
On Saturday they were missing arguably their player of the season in Leroy Millar while his midfield partner James Knowles is also recovering from a virus. With new signing Ryan Harpur unavailable, it could mean another stint in midfield for beanpole striker Adam Lecky, whose long limbs more than filled the void of the missing players in Saturday's 3-1 win over Newry City.
That result showed another side to Ballymena, having to roll up their sleeves and see off a gutsy Newry before pushing ahead in the latter stages and, with Crusaders and former Sky Blue favourite David Cushley in particular firing on all cylinders, it will be a massive test for them.
"It's another opportunity for us to see where we're at," added Jeffrey. "The long and short of it is that Crusaders have a squad which is quality in depth.
"It's ironic that when we played in the League Cup semi-final and they made some changes but gee-whizz did you see their bench, never mind what was on the pitch that day.
"And that is testimony to Stephen Baxter and Crusaders, who have been able to build that resource over a number of years. It didn't happen in a year or two or three years, it happened over 10/11 years and that's the challenge. But we go there and we're going to give our best and see where we end up, it's as simple as that."
And despite their amazing run, they will go into today's game as underdogs, but that doesn't matter a jot to Jeffrey, who loves nothing more than upsetting the odds.
"There has never been an inferiority complex since Bryan (McLoughlin) and I have been around the club, that's been part and parcel of the culture. Now people have caught up with us," he added.
"While we are not getting carried away with where we are, at the same time we are not being churlish and we are not going to say we aren't enjoying being top of the pile.
"There's a long way to go but it's nice to know that, for this week at least, Ballymena are the best team in the league."
On Saturday, Jeffrey confirmed the arrival of goalkeeper Jordan Williamson from PSNI.
"When we had the injury to Ross (Glendinning) we were in the situation of having two younger goalkeepers, and our concern was never about ability but more about experience," he said. "Jordan had offers from several clubs and the fact he chose to progress his career at Ballymena United is most pleasing. Now Jordan coming in gives us incredible strength and depth in a specialist position.
"We don't have players in our squad to warm benches, in any position, now it is up to each of the goalkeepers to work hard and push each other on to higher levels."