MK Dons manager Robbie Neilsen said there were things his side could have done better after losing 2-0 to Coventry City at Nuneaton Town.
The Scot, told his club's website: "Some good stuff, some bad. It's a bit of fitness and some stuff we could have done better.
"We did well but we need to be more aggressive.
"However, the first league game is the most important things and we have been doing double sessions but we've had another ninety minutes under our belts."