Opting to bat first on an excellent batting track, Pakistan built a competitive total around a 107-run fourth-wicket partnership between Yousuf and captain Shoaib Malik (56) but fell a few runs short of setting an imposing target for the tourists.
Yousuf followed up his 53 in Thursday's series opener to register a 13th one-day century, limiting himself to just nine fours in his 143-ball innings worth 117 runs.
Overlooked for last month's Twenty20 World Cup, Yousuf fell in the penultimate over bowled by Albie Morkel, who also had Abdul Rehman caught by Herschelle Gibbs two balls later.
Trailing the five-match series 1-0 after Thursday's 45-run defeat in Lahore, Pakistan put on 78 in their final 10 overs to compensate for a poor start.
Makeshift opener Kamran Akmal fell without scoring in the first over, playing on to a ball from Shaun Pollock that kept low while Imran Nazir (2) pulled Makhaya Ntini straight to Johan Botha at square leg.
Yousuf and Younis Khan (32) revived the innings with some smart play before the latter was run out with the score of 73.
Malik than took charge with some glorious shots as he waded into off-spinner Botha, hitting him for two sixes, and lifted Jacques Kallis straight over his head as the scoring tempo picked up dramatically.
Malik hit four sixes in his 52-ball knock.
Yousuf then put on a quick 41 from 36 balls with Misbah-ul-Haq, who hit Botha for two sixes in his cameo 21 before being dismissed by Ntini.
The aggressive Shahid Afridi hit Kallis for a big six before falling in the same over to a brilliant catch by Charl Langeveldt.