JAMES Henry knew fine margins would decide Oxford United’s clash with play-off rivals Plymouth Argyle.

The U’s were beaten 1-0 at Home Park to fall out of Sky Bet League One’s top six, as Joe Edwards’ 56th-minute volley secured victory for the side fourth in the table.

United had the better of the first half and should have reached the break ahead, with Argyle goalkeeper Mike Cooper thwarting Gavin Whyte one-on-one in the visitors’ best opportunity.

THE VERDICT: Fine margins and big decisions make the difference in promotion fight

The Northern Ireland international was later fouled in the penalty area by Plymouth’s Ryan Law, only for the linesman to raise his flag in a dubious offside call.

Henry felt the decision could have gone the other way, but would not pin the result on that moment.

He said: “From our angle it looked like Matty (Taylor) was off and Gav was on.

“You’re going to get (some of) them, you’re not going to get (some of) them.

“We created some really good chances in the first half and we didn’t take them.

“It’s always going to be difficult coming to another good side and they’re a good side, there’s no two ways about it.”

Argyle had gone more than eight hours without conceding at Home Park even before kick-off, but United had the chances to end that record.

Taylor lifted a volley onto the roof of the net shortly after Whyte’s effort, while Billy Bodin was then denied by Cooper and fired just wide early in the second half.

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But Argyle looked stronger after Edwards gave them the lead and United’s best late chance came when Taylor threw himself at Henry’s cross and handled the ball.

The midfielder, on as a second-half substitute for his first appearance since February 26, knew Plymouth would make it tough for the U’s after going ahead.

He said: “We always believe we can get back into any game if we go a goal down.

“It hasn’t happened that often this season, we’ve been that good.

“It was difficult to get back into the game – Matty’s chance was probably the only good one that was close.

“They’re a good side and when two good teams are playing each other it’s always going to be tight, no-one’s going to run away with 4 or 5-0s.

“Whoever gets the first goal is ultimately always in a strong position.”

The win was a huge boost to Plymouth’s play-off hopes, with players and fans celebrating wildly at the final whistle.

Henry said: “You heard the noise and it spurs you on, because that’s what we want.

“We want to be in those play-offs again and see where it can take us.

“There’s no reason why we can’t make a late surge.”