Shadab Khan produced an outstanding debut performance as Pakistan defeated West Indies by six wickets in the first fixture of a four-match T20 international series at Kensington Oval in Barbados on Sunday.

Brought on as the fifth bowler after the hosts were put in on a bright, breezy afternoon, Shadab's mesmerising mixture of leg-breaks and googlies earned him figures of three for seven, the most economical ever in the history of T20 international cricket in a complete four-over spell.

World champions West Indies only managed to get into three figures thanks to an unbeaten 34 from captain Carlos Brathwaite.

He dominated a 37-run eighth-wicket partnership with fellow-Barbadian Jason Holder, who was dismissed off the last delivery of the innings.

Shadab removed opening batsman and wicketkeeper Chadwick Walton and dangerous middle-order strokeplayer Lendl Simmons in his first over before adding the scalp of Sunil Narine in his second.

Kamran Akmal, back in the national T20 side after an absence of three years, deprived the newcomer a fourth wicket when he failed to hold on to a diving catch at backward point offered by Kieron Pollard.

For all the struggles they faced against Pakistan's talented and varied bowling attack, the home side's troubles started when Evin Lewis was run out in the third over of the match by Ahmed Shehzad's direct hit from 40 metres out as the batsman attempted to complete a second run.

Marlon Samuels, man of the match in two World T20 finals, was unfortunate to be adjudged leg-before to Pakistan's other slow bowler, Imad Wasim.

Thereafter it was a combination of impatience and poor shot selection which the visitors capitalised upon to take the advantage at the halfway point of the match.

Rovman Powell, like Shadab making his T20 International debut, failed to have an immediate impact with the bat as he fell to fast-medium bowler Hasan Ali.

Pakistan reached their target off the first ball of the 18th over with Shoaib Malik hitting an undefeated 38 with Babar Azam and Kamran Akmal scoring 29 and 22 runs respectively, helping Pakistan take a 1-0 lead into the series.

Shadab Khan was named man of the match for his stellar debut performance.

Earlier, the captain of Pakistan's limited overs team, Sarfraz Ahmed, said he was confident the national cricket team will outperform its host in the T20 series, ESPNcricinfo reported.

Read more: Pakistan to play four T20s during West Indies tour

The four-match T20 series started in Barbados on Sunday and will continue in Trinidad and Tobago on March 30, April 1 and 2. The limited-overs' captain said he was "optimistic" about the shake-up in the team that will play the four-match series in the Caribbean.

Sarfraz said that it was an "advantage" for the players as they are well-prepared, given they just finished playing the Pakistan Super League (PSL).

"PSL is an advantage as the boys are coming through playing T20 cricket. Many players who performed have been rewarded. I think it's a good sign that PSL is happening and players who are performing in domestic are being selected," the skipper added.

"[Legspinner] Shadab [Khan] did well, so did [left-arm pacer] Usman [Khan], so it's good to have top performers such as these boys coming through; this event is helping us unearth talent," the one-day captain said.

When asked about the change at the top order with Sharjeel Khan and Khalid Latif charged with corruption allegations, Sarfraz said, "Morale of our team is very good and boys are working hard."

Cricketers Kamran Akmal and Ahmed Shehzad will be replacing the two big names in the series.

"We are all impressed with Kamran's performance," Sarfraz said. "The way he had been scoring runs continuously over the last two years is outstanding. With his recent form in the PSL, I am optimistic that he can carry his form here and contribute and win it for Pakistan."

Sarfraz hoped the shake-up of players at the T20 leagues will serve as an advantage for Pakistan.

"Four to five senior players have been playing their league [the Caribbean Premier League] in the West Indies and this is an advantage. It's a good thing for us that these boys can easily adjust in these conditions," he said.

"It's an important series and the first match will set a tone for the series."