Nigeria's young side is one victory away from qualifying for the 2020 ICC Under-19 Cricket World Cup, after yet another commanding performance in the African qualifying tournament in Namibia.

They made it four victories on the trot, as they hammered Tanzania by 151 runs on Thursday. Olayinka Olaleye made a 110 not out at the top of the order, reaching three figures with a terrific, straight six.

His opening partnership with Sulaimon Runsewe was worth 97, and that set Nigeria on their way. Isaac Danladi struck 31 at number three, as Nigeria eventually reached 211 for three.

Tanzania were then put under constant pressure by Nigeria's pace attack, led by the left-arm star, Mohameed Taiwo. He settled for two for 20 this time, while Peter Aho returned encouraging figures of three for 7 in eight overs.

But, it was captain Sylvester Okpe who really did the damage, his off-spin reaping four for 19, including the match-winning scalp. If Nigeria can defeat Sierra Leone in their final game, they will head to their first ever U19 Cricket World Cup.

The one team that could still catch Nigeria are hosts Namibia, who also had a commanding victory, on their Day of Independence. Namibia again breached 200, as skipper Divan la Cock fell nine short of a third Namibian century this week.

His 91, as well as 55 from opener Henry Brink and 50 not out from the in-form Matthew de Gouveia, saw the hosts close on 250 for five. Uganda were still nursing the after effects from the capitulation against Nigeria the day before, but they did show some character.

Zephania Arinaitwe blazed a terrific 69 from just 30 balls at the top of the order, to give the hosts something to consider. But, even as he flayed, wickets were falling at the other end, and he could never get anyone to stay with him.

Mell Theunissen and the evergreen Mauritius Ngupita took three scalps apiece, as Namibia closed in, and eventually overwhelmed the Ugandanís by 109 runs.

The third game of the day was the real thriller, however. Kenya and Sierra Leone have had a quieter time of it thus far, but they came to life when they met. Sierra Leone notched an impressive 225 for seven, with George Ngegba leading from the front with 69 from just 58 balls.

There was also a very necessary 41 from 13-year-old John Bangura, which proved crucial in the final reckoning. Chernoh Bah battered 32 not out from 15 balls at the death, with four sixes, to lift his side beyond 200.

In their chase, Kenya stayed interested for a long time. Dilan Shah's 74 not out was the backbone of the challenge, but he eventually ran out of partners. Satish Hirani's 22 looked like it might be the companionship Shah needed, but Hirani was one of Charles Kargbo's six victims, in an outstanding spell.

He would end with six for 32, claiming the final scalp to confirm a hard-fought victory for his side. Shah was left stranded at the other end, helpless against the carnage, as Sierra Leone prevailed by 31 runs.

Friday is a reserve day in the tournament, before the final round of fixtures on Saturday.

Scores in brief:

Nigeria v Tanzania
Nigeria 211 for three (O Olaleye 110 not out, S Runsewe 43, I Danladi 31)
Tanzania 60 all out (S Saidi 20, S Okpe four for 19, P Aho three for 7)
Nigeria won by 151 runs

Namibia v Uganda
Namibia 250 for five (D La Cock 91, H Brink 55, M de Gouveia 50 not out)
Uganda 141 all out (Z Arinaitwe 69, M Ngupita three for 21, M Theunissen three for 35)
Namibia won by 109 runs

Sierra Leone v Kenya
Sierra Leone 225 for seven (G Ngegba 69, J Bangura 41, C Bah 32 not out)
Kenya 194 all out (D Shah 74 not out, C Kargbo six for 32)
Sierra Leone won by 31 runs