A late Ryan Mendes penalty helped Cape Verde overcome Mauritania to book a place in the quarter-finals of the Africa Cup of Nations for just the second time.
The game looked set for extra-time until Cheick Elwely's careless defensive header inadvertently played in Benchimol, who was brought down by goalkeeper Babacar Niasse.
Captain Mendes did the rest, smashing his spot kick hard down the middle in the 88th minute.
The result sets up a quarter-final against either Morocco or South Africa on Saturday (20:00 GMT).
Both teams had chances in a lively and fully committed encounter, leaving everything out on the field in Abidjan - but the match ultimately lacked real quality, especially in the final third.
Playing in their first-ever Nations Cup knockout game, Mauritania looked full of energy early on, with livewire runners bursting from deep, the lustrous gold trim and numbers of their kit sparkling in the late afternoon sunshine.
But it was Mendes who nearly broke the deadlock after nine minutes, racing on to a long ball over the top and lifting a delicate lob from distance over the despairing Niasse but wide.
It would have been a stunning opener.
After the fast start, the game turned scrappy midway through the first half and it was Lions of Chinguetti head coach Amir Abdou who began catching the eye more than the players on the pitch.
A nervous ball of energy dressed all in black, the man who also led Comoros to the last 16 in Cameroon two years agonever stopped marching back and forth in his technical area, gesticulating and barking instructions.
With most of the crowd backing Abdou's side, Mauritania dominated the early stages of the second period.
Aboubakary Koita put a direct free-kick on to the roof of the net before Souleymane Anne wasted his team's best chance just before the hour mark.
As Cape Verde's defence looked to block another surging run into the penalty area, the ball fell kindly to Anne, who blazed his left-footed effort high and wide when it looked easier to score, leaving the forward lying star-shaped on the floor in disbelief.
With extra-time beckoning, and with Mauritania beginning to tire, it was the Blue Sharks who pushed hardest for a winner.
Garry Rodrigues' powerful drive stung the palms of Niasse, parrying the ball as far as Jovane Cabral, who then saw his follow-up blocked.
From the resulting corner, Mendes' glancing header was also well saved.
But Cape Verde's all-time appearance holder was not to be denied, calmly converting the crucial penalty when it arrived to also extend his record as his country's leading goalscorer.
Ten minutes were added on but Mauritania never looked like finding an equaliser, meaning Cape Verde claim their first knockout win at an Afcon.
Latest Stories
-
Which will you vote for in 2024 Election: Honesty, Character, or Campaign Promises?
3 hours -
The ball is in Iran’s court after US pressure pays off
3 hours -
‘Japa’ sweeps Nigeria’s hospitals
4 hours -
Obuasi: Catholic Voices GH choral peace concert unites NPP, NDC
4 hours -
Lordina Supports NDC campaign in Ketu North with donation of medical equipment to Afife Health Centre
4 hours -
MTN Foundation delivers crucial technology tools to Eastern Regional Hospital
4 hours -
Galien Forum Africa: Enhaning African women’s role in climate and environmental crises
10 hours -
7th Galien Africa Forum ends with emphasis on health, innovation, and climate action in Africa
10 hours -
Ruthless Barcelona thrash Real Madrid to go 6 points clear
10 hours -
National Farmers’ Day scheduled for November 8
11 hours -
Samson’s Take: Why over 75% vote but only 5% join protests
12 hours -
Krachi East Chiefs applaud Bawumia for campaigning on issues with evidence
13 hours -
National Security Ministry dismisses Reuters’ claims that militants are using Ghana as logistical base
13 hours -
BOST and its CEO win big at 8th Ghana Energy Awards
14 hours -
Accused person in protest over alleged $3m BOST scandal discharged
14 hours