Cardiff head into the Arms Park clash sitting second in the United Rugby Championship after winning five of their opening six matches, a return that has fuelled confidence around the squad.
But van Zyl insists recent results are only meaningful if they continue to drive standards forward, particularly in the heat of a Welsh derby.
“Obviously it’s easier to look back at things when you’re getting results, so it’s positive at the moment,” said van Zyl.
“But it’s not worth looking too far ahead. This game this week is the most important thing.
“It’s nice to see (our league position) and a good place to be in, but it’s impossible to say where you’re going to end up. You have to take it week by week. Ultimately it’s just the next game that matters.”
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Cardiff’s recent performances, including back-to-back wins over Zebre and Ulster, have created a sense of forward motion within the camp, something van Zyl believes is beginning to show.
“We spoke about the momentum after Zebre, which pushed us in the right direction, and then we fed a lot of positives into Ulster. There’s definitely momentum building, but again, it’s about this week.”
That momentum will be tested by a Scarlets side Cardiff have not beaten at home since January 2021, a statistic van Zyl is well aware of, but one he sees as part of the challenge rather than a burden.
“We’re fully aware it’s been a long time since we beat them here. But there are things to be excited about. It’ll be packed, they’ll bring a lot of supporters, and that’s what derbies are about.
“We’ll go out, put our game on the pitch, and show what we can do.”
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Strong form across the squad has also sharpened competition for selection, giving the coaching staff plenty to ponder ahead of a high-intensity Friday night encounter.
“It’s a really big challenge for the coaches to get it right,” van Zyl admitted.
“The squad is in a good space, medically and physically, and that’s a real credit to the staff and the players.
“The growth, the fight and the enjoyment are always in the forefront of our minds.
Everybody buys in and there’s a fight for the jersey. That’s where the strength of the group is at the moment.”
The Scarlets arrive in the capital with confidence of their own after recent positive results, including an impressive win over Glasgow, and van Zyl is under no illusions about the test awaiting Cardiff.
“They’ve got momentum, a lot of experience, and a good balance between forwards and backs,” he said. “There’ll be a lot of aerial contest and some very exciting outside backs. We’ll have to be at the top of our game to be in contention.”
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