Sean Crocker and David Lipsky will share the lead heading into the weekend at the Trophée Hassan II after high winds made for a tricky second day at Royal Golf Dar Es Salam.
Lipsky's 70 moved him to five under alongside fellow American Crocker, who recovered from four bogeys in his first six holes to sign for a 74.
Another American in Julian Suri was then at four under alongside Australian Dimitrios Papadatos and English pair Lee Slattery and Jordan Smith.
Spaniards Jorge Campillo and Alejandro Cañizares, Italian Guido Migliozzi, Norwegian Kristoffer Reitan, Austrian Matthias Schwab and South African Erik van Rooyen were two shots off the lead on a congested leaderboard, with just 21 players under par.
Challenge Tour graduate Crocker is looking for a first European Tour win in just his 25th appearance, while Lipsky is seeking a third triumph and second of the season.
Should an American win the dagger on Sunday, it would continue a remarkable season for the United States, which already has eight wins from 18 events on the 2019 race to Dubai.
"I'm feeling good," said Lipsky. "Every part of my game is feeling really solid right now, the putter is working and I'm hitting a lot of fairways so it's a good combination. We're going into the weekend looking pretty good.
"Everything about this course tests your patience, it's really tight off the tee, the greens are tricky, with the wind swirling round it's tough so you just have to be patient out here."
Crocker began the day one shot off the lead but made a horrible start, making three bogeys in a row from the second and adding another on the sixth to tumble down the leaderboard.
The 22-year-old bounced back with birdies on the seventh and eighth but dropped shots on the tenth and 12th as compatriots Lipsky and Suri made their moves.
Lipsky started his round with a birdie but gave it back on the 13th before birdieing the 17th and 18th to turn in 35.
A bogey followed on the second but the 30-year-old got up and down from sand on the fifth and then holed a very long right to lefter over the ridge on the sixth to get to five under.
Suri made birdies on the 14th, 15th and 17th and while he dropped a shot on the second, a lovely pitch on the fifth and big drive on the eighth set up birdies on the par fives to move him within one of overnight leader Smith at six under.
Crocker, meanwhile, regained a shot on the 15th and then holed his second on the 17th - which had played as a par three in previous seasons - for an eagle to set the target.
Suri found water off the ninth tee for a double bogey and Smith had extended his advantage to two without hitting a shot.
But the 2017 Porsche European Open winner would drop shots on the first and third before finding the trees for another bogey on the seventh.
An approach to tap-in range on the tenth had him back in a share but a poor tee shot led to a bogey on the 14th before an approach to eight feet on the 16th for a birdie was followed by a bogey on the last.
Slattery made five birdies and four bogeys in a 72 and Papadatos birdied two of his last three holes to sign for the same score.
Schwab was the only player apart from Smith to get to seven under at any point as he birdied the first, second, third and fifth but he gave all those gains back on the seventh, eighth, 14th and last.
Spaniard Cañizares led at six under as he recovered from bogeys on the first and third with birdies on the fifth and seventh before dropping further shots on the tenth, 11th and 16th.
Van Rooyen matched the lowest round of the day with a 69, while Campillo and Migliozzi carded rounds of 71, and Reitan recorded a 73.
