Rhys Turner's second half strike was enough for Oldham Athletic to seal victory in their first pre-season game.
The striker struck on the 72nd minute of the game to earn Darren Kelly his first victory as Oldham Athletic manager.
Kelly named two trialists in his first starting 11 as Oldham Athletic manager.
It was the home side that started the better of the two, as Chester won a free kick on the edge of the box but it was smashed wide.
Striker Jake Cassidy, signed this summer, was proving to be a strong physical presence in attack, putting himself around.
That presence almost put Latics a goal ahead as he laid the ball back to Danny Philliskirk on 13 minutes but his shot was blocked as it travelled goalwards.
Philliskirk and another summer signing Lee Croft were linking up well on the right-hand side and they saw a lot of the first half action.
The 2014/15 Player of the Season Carl Winchester roamed the edge of the area and laid the ball into the path of Philliskirk midway through the half, but his shot again was blocked.
Just after the half hour mark, the game suddenly came alive.
A Chester man chipped the ball goalwards, which had Joel Coleman scrambling, but it fell past the post, fortunately.
A minute later, Latics raced up the other end and should have taken the lead. Cassidy got behind the defence, whipped the ball dangerously across the box and trialist was there but Simpson pulled off a great save to deny Latics taking the lead.
Latics were knocking on the door and should have taken the lead on 35 minutes through an unlikely source.
James Wilson started an attack, laid the ball to Philliskirk, who picked out the defender who continued his run and presented with an own goal, he placed the ball past the post to the relief of the Chester players.
It was a good run out for the first half team but they could not manage a goal. At half time, Kelly made wholesale changes with a trialist, Croft and Timothee Dieng the only players to remain on the pitch from the first half.
Chester started the second half brightly as it took Latics a while to get going in the second half.
Latics were struggling to get hold of the ball in the second half with the home side dictating most of the play.
Jack Tuohy was brought into the action on the hour mark and he replaced Lee Croft.
Cornell was forced into action on the 65th minute but he held the ball comfortably after a shot from 25 yards.
For all the home sides domination in the second half, it was Latics that took the lead on 72 minutes through Rhys Turner.
The 19-year-old was fed by Rhys Murphy and he took the ball past the goalkeeper and placed it into the empty goal to put Latics one goal ahead.
Edmundson, Brian Wilson and the two trialist defenders were being put under increased pressure as Chester continued to press the Latics goal.
With only five minutes remaining on the clock, George Green was allowed space to run into. He knocked it past two players, looked to be clipped inside the area, stayed on his feet but his cross was cleared away from danger.
Danny Byrnes was introduced for the last two minutes of the game as he replaced Timothee Dieng.
Latics managed to hold on to the lead and notched their first victory of pre-season.
Chester: Simpson, Tonge, Hunt, Chappel, Shaw, George, Mahon, Hannah, Thompson, Heneghan, Sharps.
Subs: Hughes, Rooney, Higgins, Kay, Peers, Hobson, Richards, Lirpitt, Vince, Heath.
Oldham Athletic first half: Coleman, Dieng, J.Wilson, Trialist, Truelove, Kelly, Winchester, Croft, Philliskirk, Cassidy, Trialist.
Oldham Athletic second half: Cornell, Trialist, Edmundson, Trialist (Bove 90'), B.Wilson, Dieng (Byrnes 88'), Green, Croft (Tuohy 61'), Trialist , Murphy, Turner.
Goals: Chester FC 0-1 Oldham Athletic (Turner 72')