The Northern Ireland Under 21s international midfielder has signed a deal until the end of the season after being released by Shrewsbury in January.
Having appeared in a couple of reserve games, Shrimps boss Bentley has been impressed with the former Barnsley man’s willingness to go the extra mile to make himself a more permanent fixture at the Globe Arena.
Bentley said: “He’s been paid up by Shrewsbury in January and, fair play to him, he’s not on the payroll here.
“He’s doing it for nothing and just wants an opportunity, much like Ryan Williams did.
“He just wants to sign, get in the squad and try and prove himself with one eye on next season.
“It’s a no-brainer to get a player for free. That’s credit to him, a credit to the way he’s thinking, his eagerness and the way he’s backing himself to earn a contract.”
McKnight was joined on the bench in the defeat at Leyton Orient by fellow new boy Cole Stockton, the big front man having joined on loan from Tranmere on Thursday.
Stockton is best known to Shrimps fans for scoring both goals in Tranmere’s 2-1 win over Morecambe at Prenton Park last season.
Bentley said: “We’ve run with two centre-forwards for the majority of the season.
“We’ve got Shaun Miller and Paul Mullin who are similar, but Cole Stockton brings something different.
“He’s more of a target man. He’s not getting in at Tranmere at the minute.
“They both bolster the squad because if we hadn’t have brought them in it would have been five on the bench on Saturday.”