Myneni, ranked 451, overcame the number 202 Belgian 1-6, 6-3, 7-6(4) in a close to two-hour second round match in the US $50,000 Challenger tournament.
The big-serving Myneni next faces his Asian Games’ silver medal-winning partner, Sanam Singh.
Sanam entered the quarter-finals with a hard-fought 4-6, 7-6(5), 6-3 win over compatriot and qualifier N Vijay Sundar Prashant after battling for two hours and 14 minutes.
The diminutive Sanam had knocked out second seed and world No 129 Russian Alexander Kudryavatsev in his opening round match on Tuesday.
Top seed from Kazakhstan Aleksandr Nedovysov also advanced with a 6-3, 6-4 win over Belgium's Germain Gigounon.
Meanwhile, the Somdev Devvarman combined with left-hander Jeevan Nedunchezhiyan to upset Thai top seeds Sanchai and Sonchat Ratiwatana 4-6, 6-4, 10-7 in the first round of the doubles event.
Image: Saketh Myneni
Photograph: PTI
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I like playing my shots and will stick to that, says Manish Pandey