Seeded eighth, the Indo-Vietnamese duo had to work to register a 7-6, 3-6, 12-10 win in the last-four match which lasted two hours and 20 minutes on Court No. 3.
They had beaten Japanese combination of Yusuke Takahashi and Jumpei Yamasaki 6-2, 6-3 on grass Court No.6 of the All England Club to reach the semi-finals.
The 17-year-old Delhi-born Nagal and his partner will take on American-Japanese fourth seeds Reilly Opelka and Akira Santillan in the title clash.
Image: Sumit Nagal of India.
Photograph: Patrick Scala/Getty Images
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