Wild-card entrant Isner lost his first matches in 2007 and 2008 in his only other visits to the Newport grass but never saw a break point over 94 minutes in his third victory this week to reach his first ATP semi-final of the year.
On Saturday, 46th-ranked Isner will face German eighth seed Tobias Kamke, who reached his first career ATP semi-final by ousting France's Edouard Roger-Vasselin 3-6, 6-1, 6-3.
Kamke, last year's ATP Newcomer of the Year, needed 98 minutes to advance, improving to 8-12 this season. He reached a career high of 64th in the rankings but has since slid to his current ranking of 96th.
In Friday's two remaining quarter-finals, Belgian sixth seed Olivier Rochus will face Australian Matthew Ebden and US qualifier Michael Yani will meet US wild-card entrant Denis Kudla.
What the stars mean:
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