The England scrum-half will make his comeback from a fractured thumb in Friday’s home Betfred Super League game against Wakefield Trinity.
Leeds have not won since their opening day win over the same opponents, losing all five of their following contests.
Gale has been absent for all but one of those having fractured his thumb in the 18-10 defeat against his former club Castleford Tigers on April 2.
With stand-off Rob Lui (quad) yet to play this term and fellow half-back Richie Myler being injured and then suspended, it is no surprise Leeds have struggled at times.
With the former Man of Steel Gale now back, Agar conceded: “It’s pretty obvious one of the elements of our game we’ve struggled with - and has been a bit of a consequence to where we are at the moment - is an inability to have a stable line-up and half backs playing in half-back roles.
“Galey’s a welcome return; he’s our captain and kicks the ball and touches the ball more than any other player we’ve got so his influence back in the team has been immediate.
“It’s given some people some confidence. He keeps it nice and simple but at the same time it’s been a very, very tricky situation for us.
“It’s been one forced upon - us changing our halves every week and having people playing out of position, some square pegs in round holes for a number of weeks.”
Leeds did not play last weekend having been knocked out of the Challenge Cup.
On Gale’s return - he is the only change to Leeds' 21-man squad, coming in for the injured centre Alex Sutcliffe - Agar added: “We got him back into training last week.
“The challenge has been holding him back.
“He’d been trying to get back a week early so the week off has almost done us a bit of a favour as the last game (a 14-13 loss at Huddersfield Giants) was too early.
“Had we’d played last week I’m sure he’d have pushed and wanted to play.
“But this has just given it the required time of what the surgeon and specialists have deemed right and correct.
“He’s trained unaffected all week.”
Ex-England half-back Kyle Eastmond has also been included in the 21-man squad after missing the Giants game with a hamstring issue.
Asked if he would play, Agar replied: “There’s a chance.
“We named him in our squad but we’ll have a look at our line-up later in the week.
“I’m not going to deny Luke will be back but we will name our line-up at our team run tomorrow.”
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