The Waterford golfer sits tied for 70th place on two-over-par heading into the final day.
Séamus Power endured a difficult third round at the Charles Schwab Challenge in Texas, slipping down the leaderboard after carding a four-over-par 74.
The Waterford golfer mixed two birdies with six bogeys during his round and now sits tied for 70th place on two-over-par heading into the final day.
American Eric Cole holds the outright lead after producing the round of the day, a seven-under 63, to move to 12-under for the tournament.
Ryan Gerard is one shot behind in second, while MacMeissner and J.J. Spaun remain firmly in contention, two shots of the pace.
Power will be hoping for a strong finish today as he looks to climb the standings and pick up valuable FedEx Cup points.

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