The Shrimps lost 2-0 against Lincoln City on Saturday, having gone into the game on the back of wins at Port Vale and Oldham Athletic.
However, they were comfortably second best at the Globe Arena and barely posed any threat to the League Two leaders.
Defeat kept Morecambe 20th in the table, five points ahead of second-bottom Macclesfield Town with a dozen games left.
The first of those comes on Saturday when the Shrimps, who sit 20th in the table, travel to a Yeovil Town side one place beneath them.
“We had little spells but not enough to deserve anything from the game,” Bentley said of their performance against Lincoln.
“We had a couple of opportunities and a couple of corner routines but you can’t expect to have a minute here or two minutes there and be off the gas for 15 minutes because you’ll get nothing from the game.
“We had a little spell second half, similar to the first, but then he (Bruno Andrade) slotted it away and that took the sting out of it.
“We came back, had a couple of opportunities, a couple of set-plays and played some good football at times but we lacked that killer instinct in the box.
“It’s disappointing, it’s unacceptable and that doesn’t reflect us.
“If we’re going to play like we played in the last two games, then we deserve every credit we got.
“However, against Lincoln, they deserved what we told them; they need to have a look at themselves but we all do.”
Bentley had opted to field an unchanged team on Saturday following on from Morecambe’s previous teams.
However, those exertions – especially on a less than perfect playing surface at Oldham – meant the Shrimps looked like a team who had played two tough games in the previous week.
“In all honesty we should have made three or four changes to freshen it up,” Bentley said.
“I could have made 11 at half-time; all I can do is apologise to the fans because they deserve better.”