Striker Matt McClure was dismissed just 30 seconds after coming on as a substitute with 20 minutes to go in the nervy 2-1 win over Tranmere Rovers on Tuesday, and Ainsworth hinted that the growing pressure of the promotion race was beginning to take its toll on his side.
He told reporters after the game: "I had a go at the boys at half-time because they changed their mental attitude after we went ahead.
"We looked like a team who were under pressure to get promoted, but we have no right to be where we are in the league with the size of the squad we have.
"We are going to go for it rather than play a game of risk where promotion is concerned.
"Nobody expects us to get promoted so we aren't under any pressure and the lads responded to that. This group of lads dig deep."
Ainsworth's men face a tough trip to play-off contenders Southend United on Saturday, with the visitors sitting just one point adrift of front-runners Burton Albion and Shrewsbury Town.
Burton travel to bottom-of-the-table Hartlepool United, having slumped to back-to-back defeats for the first time under boss Jimmy Floyd Hasselbaink – a run that has seen them knocked off the top of the table on goal difference by Shrewsbury, who host Cambridge United.
Elsewhere at the top, fourth-placed Luton Town will hope to get their play-off bid back on track at home to Morecambe, while Bury host Oxford United and Newport Country travel to Stevenage.
At the bottom, York City will be looking to build on their thumping 3-0 win over Cambridge, and pull further away from the drop zone, with a win at AFC Wimbledon, while Cheltenham could haul themselves out of the bottom two with a result at home to Mansfield Town.
Struggling Tranmere will aim to halt a three-match losing streak when they host Dagenham and Redbridge, knowing a win could see them overtake Carlisle United, who entertain Exeter City.
In the day's other games, Portsmouth travel to Accrington Stanley and Plymouth Argyle take on Northampton Town.
