Blackburn boss Allardyce returns to St James' Park tonight for the first time as a manager since he was sacked by the Magpies early in 2008 after less than a year in charge.
Allardyce said: "I have proved most of the time that when I get a football club it improves from where it was.
"That was going be the case at Newcastle but I was not given enough time, but there is no bitterness towards the club.
"I'm not sure that apart from Arsene [Wenger] and Sir Alex [Ferguson] anyone else has managed at this level for as long as I have.
"I take a huge amount of pleasure in having been able to sustain my ability in the best league in the world."
Blackburn have a number of injury problems ahead of the game, with Benjani the latest to join the list of absentees.
The Zimbabwe striker suffered a hamstring injury against Wigan at the weekend and joins Steven Nzonzi, Vince Grella and Keith Andrews on the sidelines.