Portland reached the playoffs for the fourth straight season in 2008, and for the fourth straight year the Sea Dogs faced the Trenton Thunder in the Northern Division championship series. The Thunder would sweep the Sea Dogs en route to their second straight Eastern League crown, but it was quite a winding road for Portland.

Justin Masterson was the opening day starter, and in his first two starts he had a 0-0 record with a 0.00 ERA, 10 strikeouts and zero walks in nine innings. On April 24, Masterson found himself on the mound at Fenway Park and tossed six strong innings in his major league debut. After a brief stop back in Portland and then a promotion to Pawtucket, Masterson would conclude the season as one of the most reliable arms in the Red Sox bullpen, posting a 6-5 record with one save and a 3.16 ERA.
Masterson also made nine appearances for the Red Sox in the playoffs, going 1-0 with one save and a 1.86 ERA.

On April 16, the Sea Dogs played the longest game in team history, a 17-inning marathon lasting 5 hours, 41 minutes. Jay Johnson delivered the winning hit in the bottom of the 17th to give Portland an 8-7 win, and he also was the winning pitcher. It was just the 10th time in franchise history that a position player was called upon to pitch.

The Sea Dogs sent five players to the All-Star game – pitchers Michael Bowden and Beau Vaughan and outfielders Bubba Bell, Jeff Corsaletti and Zach Daeges. Bowden and Corsaletti were promoted to Triple-A Pawtucket soon after.

The departure of Corsaletti opened the door for Lars Anderson to join from Single-A Lancaster. He reached base in 36 of the 41 games he played for the Sea Dogs, hitting .316 with five home runs (including two grand slams) and 30 RBI. Fans also saw plenty of Daniel Bard, who in 31 appearances posted a 4-1 record with a 1.99 ERA.

Perhaps the biggest highlight for fans was a three-day rehab stint for Red Sox slugger and fan favorite David Ortiz. Although ‘Big Papi’ only collected two hits, fans were still thrilled.