The Lions went down to a single goal defeat against Huddersfield Town in the first of four home games against Football League opposition.
Shaun Scannell grabbed the winner for the Terriers just before the break his well hit shot going in off the inside of the post but it was no more than the visitors deserved having already hit the post before and the bar on two occasions.
The visitors fielded two different sides in each half and included club-record signing Christopher Schindler, a £1.8m from 1860 Munich was in the starting eleven, while Guiseley gave a run out to all of their new signings and several titlists.
While the Championship side looked comfortable for most of the game Oli Johnson went close in the first half with a cross come shot and Jordan Preston foiled by the visiting keeper in a one-on-one late on.
The Lions next pre-season outing sees Bradford City providing the opposition at Nethermoor on Saturday (ko 3pm).