Lewis has led the Bengals to both of their playoff games since 1991 -- they also went in 2005 as division champs and lost at home in the opening round.
"I do need to apologize that I haven't gotten us over the hump, and I haven't gotten us beyond where we've been," Lewis said Monday at his end-of-the-season news conference. "That's my job and my focus to get us beyond that. And we'll get started on that very quickly."
Cincinnati's defense faded at the end, hampered by injuries to some of its top run defenders, but finished the regular season ranked fourth in yards allowed -- its highest ranking 1983, when it finished first. Defensive coordinator Mike Zimmer's contract expires at the end of this season.
Lewis arrived in Cincinnati before the 2003 season and has led the Bengals to their only two winning records since 1991. After Cincinnati's brief playoff appearance in 2005, Lewis had his contract extended two years through the 2010 season.
"I would imagine (Brown) and I would talk," Lewis said. "I have no timeframe of when we would talk."
Cincinnati's biggest challenge in the offseason will be improving a passing game that fell off dramatically.
The Bengals lost top wide receiver T.J. Houshmandzadeh to free agency after last season. Wide receiver Chris Henry broke his arm, then died during a domestic dispute last month. Chad Ochocinco rebounded from a subpar 2008 season, but no one else was consistent among the receivers.
Cincinnati lacks a dynamic pass receiver out of the backfield. Both of its starting tight ends -- Reggie Kelly and Ben Utecht -- had their seasons end during training camp because of injuries.
Lewis doesn't plan to change the offense's run-first identity to try to restore the passing game.
"I think we need to keep putting pieces around our quarterback to enable him to utilize all the abilities and skills that he has," Lewis said. "We've gotten some things established. We know that we have the maturity level that he has, with how to play the game. Now we have to give him the best tool belt we can to put around him and get things done."
The Bengals revamped the offensive line in the offseason -- right guard Bobbie Williams was the only player in the same spot -- and developed one of the league's top running games.
"I think we've established a strong foundation," Lewis said. "We've really kind of screwed down some pillars into the sand, which is a good thing as we move forward. Now we have an opportunity to build upon that and continue to tweak the kind of things we have to do offensively."
Copyright 2010 by The Associated Press