Sol Campbell suffered defeat in his first Sky Bet League Two game in charge of bottom side Macclesfield after they lost 1-0 at promotion-chasing Colchester.
The former England international watched his new side’s two-match winning run in the league come to an end as Mikael Mandron scored the game’s only goal.
Macclesfield’s Elliott Durrell had seen a long-range effort drop just wide early on but O’Hara then denied both Jackson and Courtney Senior in quick succession.
The Silkmen went close twice in quick succession when U’s goalkeeper Dillon Barnes parried away Danny Whitaker’s fierce strike and then Durrell headed Ryan Lloyd’s cross over from two yards.
Visiting keeper Kieran O’Hara then pushed away Mandron’s fierce effort but could do nothing as the forward struck in the 29th minute, driving in a low left-footed shot after being picked out by Ryan Jackson on the edge of the box.
Harry Pell’s 25-yard free-kick flashed wide as the hosts pushed for a second before the break.
Macclesfield battled hard in the second half and defender Fiacre Kelleher almost rescued a point for them when his header went inches wide of goal from James Pearson’s cross.
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