McIlroy holed an 11-foot eagle putt at the second and four further birdies left the Irish duo in a share of second place on 14 under after 12 holes.
However, McIlroy missed the green with his approach on 13 as they dropped a stroke and further shots went at the last two holes when they were unable to find the greens in regulation.
Saturday’s round will revert to the fourball format before Sunday’s foursomes finale.
“Tomorrow it will be hard to stay patient because the fourball format you just have to try to make as many birdies as you can,” added the Masters champion.
Velo and Salinda lead their fellow US players Ben Griffin and Andrew Novak by one shot, with Danish twins Rasmus and Nicolai Hojgaard a further stroke off the pace.
English pair David Skinns and Ben Taylor share fifth spot four off the pace after firing a 67 on Friday with their compatriot Aaron Rai and US player Sahith Theegala one shot further back.
Scotland’s Robert MacIntyre and his Belgian partner Thomas Detry share 16th place in the group that includes McIlroy and Lowry after firing a 69 on Friday.
The fourball element sees both players hitting their own ball with the best score counting, while players take alternate shots with one ball in the foursomes.