Griquas and Western Province go into battle in Kimberley on Friday with the losers almost certainly missing out on the semi-finals.
Only one point separates these two teams in the standings with Griquas currently in fourth place on the table with 19 points from six matches and WP in fifth spot after the same number of games.
Griquas have been the surprise package this season and have impressed with their enterprising style of play.
They caused arguably the biggest shock of the tournament when they beat the defending champions, the Golden Lions, 30-24 in an exciting encounter in Kimberley in Round Three.
That was their first match at their home ground and they have subsequently gone on to register comfortable victories in their other home fixtures against the Eastern Province Kings and Boland Cavaliers respectively.
Despite those fine results in Kimberley, Griquas head into this clash after suffering a humiliating 57-20 loss to the Blue Bulls in Pretoria in the previous round.
Their head coach Peter Engledow has made four changes to his starting line-up after that defeat. The only change in the back-line sees JW Jonker taking over from Alshaun Bock on the wing.
In the pack, Jono van Rensburg replaces Jason Fraser at number eight while Wandile Putuma and former Springbok Hilton Lobberts form a new second-row combination. They take over from Jonathan Janse van Rensburg and Mzwanele Zito.
Unlike their 2014 and 2015 campaigns – when they finished as tournament winners and runners-up respectively – 2016 has been a disappointing season for Western Province.
They beat the Pumas 31-23 last weekend but it was a hard slog for the 2014 champions as they only sealed their win in the last 20 minutes. WP have battled throughout the season but it hasn't been all doom and gloom for them and if they can replicate their Round Five performance against the Sharks, when they claimed a 34-27 win at Newlands, then they can end Griquas' winning run in Kimberley.
The men from the Cape received a shot in the arm with the return of Springbok duo Juan de Jongh and Bongi Mbonambi but despite that their coach John Dobson expects Griquas to ask some serious questions of his team this weekend.
"They have got their 130th anniversary, and they are having a great season," he told WP's official website.
"They have said before this game that they are targeting the Western Province game, so we are under no illusions.
"It is a quarter-final for us, and again they are a big, older pack, and some really good strike runners. They are a big, physical team, but I think we are much more alive for it and confident than we were a few weeks ago."
The last time these teams met: Western Province claimed a narrow 24-23 victory during their Currie Cup Qualifier at Newlands in Cape Town. WP had to dig deep though, after trailing 10-13 at half-time but eventually outscored Griquas by three tries to two.
Prediction: Don't be surprised if this game goes down to the wire as these sides are evenly matched. WP will be boosted by the return of their Boks but home ground advantage will be decisive. Griquas to win by three points!
Griquas: 15 AJ Coertzen (c), 14 JW Jonker, 13 Johnathan Francke, 12 Clinton Swart, 11 Ederies Arendse, 10 Elgar Watts, 9 Rudi van Rooyen, 8 Jono van Rensburg, 7 Sias Koen, 6 Wendal Wehr, 5 Wandile Putuma, 4 Hilton Lobberts, 3 Stephan Kotze, 2 AJ le Roux, 1 Steph Roberts
Replacements: 16 Marius Fourie, 17 Devon Martinus, 18 Jonathan Adendorf, 19 Jason Fraser, 20 Renier Botha, 21 Andre Swarts, 22 Eric Zana
Western Province: 15 Cheslin Kolbe, 14 Werner Kok, 13 Juan de Jongh, 12 Huw Jones, 11 Leolin Zas, 10 Robert du Preez, 9 Dewaldt Duvenage, 8 Nizaam Carr, 7 Kobus van Dyk, 6 Rynhardt Elstadt, 5 Chris van Zyl (c), 4 Jan de Klerk, 3 Wilco Louw, 2 Bongi Mbonambi, 1 JC Janse van Rensburg
Replacements: 16 Mike Willemse, 17 Alistair Vermaak, 18 JP Smith, 19 Dave Ribbans, 20 Jurie van Vuuren, 21 Jano Vermaak, 22 Johnny Kotze
Date: Friday, September 23
Venue: Griqua Park, Kimberley
Kick-off: 19:00 local (17:00 GMT)
Referee: Jaco Peyper
Assistant Referees: Lourens van der Merwe, Jaco Kotze
TMO: Marius Jonker