Walter Mazzarri was hired last May to turnaround Inter Milan after a ninth place finish last season under Andrea Stramaccioni.
But after a promising start to the season, Inter is in a battle to qualify for the Europa League.
Inter is winless over their past four matches.
"It's [been] an unusual year," Mazzarri said ahead of Sunday's trip to Sampdoria. "There haven't been many games that we didn't deserve to win.
"I've never seen the team really struggling. In fact, we've often picked up less than we deserved.
"We've often determined the course of games with the approach we've taken, that can be seen as a positive.
"I know we'll get back to being a competitive side with working methods that are different to the past.
"We've let teams peg us back after going ahead. That's the area where we need to make the biggest improvement."