RENTON, Wash. (AP) Pete Carroll has regularly stressed the importance of winning the turnover battle as a key indicator of a team's success.

''It's all about the ball'' has been a frequently heard phrase throughout the headquarters of the Seattle Seahawks since Carroll took over the franchise in 2010, an effort to stress to players the need to keep the ball on offense and take it away on defense.

That's what makes the first five games of the 2015 season so baffling for the Seahawks coach. Seattle has lost two games while winning the turnover battle and won a game while losing the turnover battle so far this year.

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It's an oddity that Carroll can't quite wrap his head around.

''I don't understand it,'' Carroll said. ''It doesn't make sense to me. Usually, when you control the football, you win. Our stats aren't supporting that for the first time in 14 years, you know? It's really odd, and I can't imagine that it'll stay the same. It should turn. All of the principles and the odds of that just aren't in the right direction right now.''

Seattle won the turnover battle 3-1 against the St. Louis Rams in the season opener and lost 34-31 in overtime. The Seahawks won the turnover battle 2-1 last week in Cincinnati and lost 27-24 in overtime. They also beat the Detroit Lions in Week 4 despite losing the turnover battle 3-1.

''I can't register that,'' Carroll said. ''That doesn't fit in my brain. I don't know that. Years and years and years, and it doesn't fit. All I think of is that's going to flip-flop the very next chance we go out, and it hasn't yet.''

The numbers this season back up Carroll's thoughts as well. The Indianapolis Colts are the only team in the league to hold a winning record despite a negative turnover differential. Sixteen teams have a negative turnover differential and are a combined 23-55.

''It's very odd,'' wide receiver Doug Baldwin said. ''Even if you look at the statistics across the NFL, it usually doesn't happen that way.''

Fourteen teams have a positive turnover differential for the season and are a combined 50-16. Each game played is a separate event with separate variables that lead to different results, but on a large scale it's clear how important turnover margin is to success.

''Usually in the past, when we win the turnover ratio we always win,'' safety Earl Thomas said. ''But it's a new season. We'll figure it out.''

Carroll's theory should be put to test again this week as the Carolina Panthers come to Seattle. The Panthers lead the league in turnover differential. Their plus-8 turnover margin is two turnovers clear of the rest of the league and cornerback Josh Norman is tied for the league lead with four interceptions. Keeping control of the football will be a premium for Seattle on Sunday.

''They're getting turnovers galore,'' offensive coordinator Darrell Bevell said. ''A lot of interceptions from the corners, from the linebackers. I think they're playing great all over the place.''

Notes: RB Marshawn Lynch (hamstring) and LB Kevin Pierre-Louis (hamstring) returned to full participation in practice on Thursday after missing the last two games due to injury. ... LB Nick Moody, added from the practice squad on Wednesday, did not practice due to an ankle injury. ... DE Demarcus Dobbs (shoulder) returned to limited participation after missing the last two games.