The 2009 MLB season just ended. The Yankees racked up yet another World Series win, and the Mariners were mediocre at best. But there are already reasons for Mariners fans to get excited for next season.

The Kid is back again.

Ken Griffey Jr. is back for what will probably be his last season in the big leagues. Yesterday, the M’s announced that Junior will be joining the team again next year, making around the $3.15 million he made last year.

But did the Mariners make the right decision to bring back Junior, especially after last year’s performance?

The 39-year-old lefty hit a measly .214, while hitting 19 home runs and racking up 57 RBI. Yet his affect on the team extended further than the stat sheets.

Without Griffey, the 2009 season may have ended in disaster. Prior to his arrival, the clubhouse was somber and lacked any excitement or cohesiveness.

With rookie manager Don Wakamatsu leading the way last year, no one really knew how the team chemistry would play out. But Griffey took on a leadership role and, off the field, played pranks on his teammates bringing a newfound energy to the clubhouse.

He even had a huge effect on the best player on the team. All-Star Ichiro Suzuki, who grew up in Japan adoring Junior, had been notorious for being a selfish and detached teammate. Griffey single-handedly changed that. The somber, serious Ichiro fans were used to changed into an energetic, friendly teammate. It rubbed off on the field, too; the 2001 MVP hit .352 and had 200 hits for the ninth-consecutive season, a new record.

Said General Manager Jack Zduriencik in a conference call yesterday: “His influence, the presence he has ­— there are players on this ball club who are very excited to know they are going to be teammates again with Ken Griffey Jr.”

Griffey won’t be a huge threat on offense or defense, but that’s not the point. If the M’s can land a few big hitters and add some depth to their pitching staff, they could challenge the Angels for the AL West crown. Signing Griffey for one more year won’t hurt that cause.

The truth is, Junior means a lot to this ballclub. He is a clubhouse leader and he brings fans to the ballpark. Currently sitting in fifth place on the MLB career home run list with 630, the Mariners legend is one of the best players to ever put on an M’s jersey. And any time you have a Hall of Fame presence in the clubhouse, it’s a good thing.

For $3.15 million, having that type of player on the team is well worth it. Also, by getting this out of the way early in the off-season, the team will create less drama and distractions come spring training.

The Mariners went from winning 61 games in 2008 to winning 24 more in 2009, as they finished 85-77. Zduriencik must be doing something right, and signing Griffey no doubt helped.

Here’s to Junior and Co. winning 24 more next year.

Reach columnist Taylor Soper at sports@dailyuw.com.