Japan's doubles pair came from a set down to defeat an experienced Pakistan duo in the Davis Cup World Group I first-round match in Islamabad on Saturday, booking a place in the 2022 qualifiers.

Shintaro Mochizuki and Sho Shimabukuro beat Aisam-ul-Haq Qureshi and Aqeel Khan 4-6, 6-4, 6-2, in one hour and 47 minutes.

Adding to their wins in both of Friday's singles clashes, Japan took an unassailable 3-0 lead in the tie overall.

They will fight for a place in the Davis Cup via next year's qualifiers, while Pakistan head for the World Group I play-offs.

After the singles victories, Japan gave a debut to young Shimabukuro, partnering former Junior Wimbledon champion Mochizuki in place of their number-one player Yosuke Watanuki.

The gamble paid off despite Qureshi and Khan pulling off the first set 6-4 and looking threatening in the second, but the home pair lost their energy once the Japanese duo took the attack to them.

After a late break in the second set, the Japanese pair broke early in the third, in a tie played without spectators due to Covid-19 restrictions.

The reverse singles will be played on Sunday. 

Result:

Davis Cup Group I first round: Japan 3, Pakistan 0

Shintaro Mochizuki and Sho Shimabukuro (Japan) beat Aisam-ul-Haq Qureshi and Aqeel Khan (Pakistan) 4-6, 6-4, 6-2 

On Friday:

Yosuke Watanuki (Japan) beat Aqeel Khan (Pakistan) 6-3, 6-2 

Kaichi Uchida (Japan) beat Aisam-ul-Haq Qureshi (Pakistan) 6-4, 7-6 (7-4)