Veteran Afghanistan all-rounder Mohammad Nabi scored seven off three balls in the final over at Harare Sports Club to deliver a three-wicket Twenty20 win over Zimbabwe on Saturday, and a 2-1 series victory.

Nabi struck a four off the first ball, followed by a two and a single in a tense finish as the tourists followed up a 50-run triumph on Friday.

Nabi finished unbeaten on 24 -- the second best Afghan batter after another all-rounder, Azmatullah Omarzai, who made 34 after taking two wickets.

Zimbabwe posted 127 in 19.5 overs and Afghanistan 128-7 with three balls to spare as they won a sixth consecutive T20 series against the southern African nation.

"In the middle of our innings we lost some wickets cheaply which put pressure on us," Nabi told reporters.

"But I managed to control my nerves and that gave me the confidence to go on and score the series-winning runs.

"Next up is the one-day international series and this wicket is not easy to judge. The pitch for the first two games was better -- today it was up and down."

Afghan captain Rashid Khan won a third straight toss, but after batting first in the earlier matches, he opted to bowl in the series decider.

Khan took 4-27 for Afghanistan while opener Brian Bennett top scored for Zimbabwe with 31, including four fours.

Afghanistan struggled in reply, losing four wickets for 44 before a 48-run fifth-wicket stand between Omarzai and Gulbadin Naib (22) tilted the balance toward the visiting team.

From then on the tourists looked the likelier winners, but when Omarzai was caught and bowled by Sikandar Raza with 13 balls remaining, there was a glimmer of hope for the home team.

But Naib dashed those hopes with his 18-ball knock, which included three fours.

Batters struggled with neither team managing to score a six while Zimbabwe hit 11 fours -- two more than Afghanistan.

The teams now play a three-match one-day international series in Harare, starting on Tuesday, then two Tests in Bulawayo.

Brief scores

Zimbabwe 127 in 19.5 overs (B.Bennett 31, W.Madhevere 21; Rashid Khan 4-27, Azmatullah Omarzai 2-10, Mujeeb Ur Rahman 2-20, Naveen-ul-Haq 2-27) v Afghanistan 128-7 in 19.3 overs (Omarzai 34, Mohammad Nabi 24 not out, Gulbadin Naib 22; B.Muzarabani 2-19, Sikandar Raza 2-19, T.Gwandu 2-30)

Result: Afghanistan win by three wickets

Series: Afghanistan win 2-1

Toss: Afghanistan