The side defeated Matavera in a do-or-die clash on Saturday to ensure their spot in the top four and finish on top of the round robin competition.
Matavera opted to bat first and struggled to find its footing, losing three wickets for just 12 runs.
The side managed to stabilise their run rate with Iro Maroroa (23 runs), Morgan Morgan (24) and Moni Uini (26) doing well with the bats to amass the much needed runs.
However tight bowling from Daniela Vailoa, Junior Ngatokorua and Kanute Ritaua, who all collected three wickets each, restricted Matavera to just 131 runs.
Tupapa, knowing a loss could possibly put them out of the competition, remained unfazed despite some brilliant bowling from Matavera.
Wayken Punga and Parker Daniel put on an impressive performance to record a match winning partnership of 111 runs.
Punga playing the anchor role with his 26 not out while Daniel booming his way to 75 not out.
Tupapa managed to overcome the target in 15.4 overs, ensuring they went top of the table and remain on track of a successful title defence.
In other important matches, Titikaveka Titans defeated Tupapa II, Turangi overcame Nikao, Muri beat Avana and the Arorangi Red Backs toppled Takuvaine.
“At the weekend’s conclusion of The Computer Man round robin, the Titikaveka Titans, Turangi and Matavera have all joined Tupapa to progress to the coveted top four playoffs,” Cook Islands Cricket chief executive officer Alister Stevic said.
“The remaining six teams in the competition split off into a bottom six knockout competition.”