PORTLAND – After they had to put off Opening Day for the first four days of the season, the Portland Sea Dogs didn’t want to leave their fans waiting any longer. They didn’t seem to mind leaving their baserunners waiting, though.

The Sea Dogs began defense of their 2006 Eastern League championship by outhitting the New Britain Rock Cats, 12-10, but left 13 men on base and dropped an 8-6 decision at Hadlock Field Monday night.

Less than half of the 3,802 paying customers braved the cold (41 degrees at game time) to watch the Sea Dogs go 3-for-17 and strand at least one runner in scoring position in every inning but the seventh and ninth.

“For the first time out, it was nice to get men on base,” said Portland manager Arnie Beyeler, whose team played six innings of a simulated game against Single-A affiliate Lowell on Sunday but hadn’t seen live pitching for more than a week before that. “The guys didn’t let up and played hard the whole game. We scored some runs, played pretty good defense and pitched pretty well when we needed to. They just threw a few more crooked numbers up than we did.”

Leadoff hitter and prized farmhand Jacoby Ellsbury, the top prospect in Boston’s minor league system, used the whole ballpark en route to a 4-for-6 night with three doubles, an RBI and one run scored.

“We came out of the gates swinging, especially this being the first game and having four days off,” Ellsbury said. “Even in batting practice, it felt like my timing was a little off, but the only thing else that could have gone right (in the game) was getting a win.”

“He’s an exciting player and did what everyone everybody expects him to do,” Beyeler said. “He used his speed. He played good defense out there tonight. He drove some balls and showed everybody the kind of player he is.”

David Bacani, the lone player from last year’s opening day lineup, belted a two-run homer and had two hits, as did Jed Lowrie and Cory Keylor.

Portland had to battle back from a 7-1 deficit to keep it interesting for those fans who stuck around. Sea Dogs starter Tommy Hottovy got behind too many hitters in the second inning and put the Sea Dogs behind in the process. David Winfree drew a one-out walk, then scored on Brock Peterson’s double into the right-center field gap. Luke Hughes then clubbed a double over Ellsbury’s head in center and came around on Kyle Geiger’s seeing-eye single into left to make it 3-0. Portland threatened in the bottom of the frame but stranded runners at second and third against New Britain starter Brian Duensing.

The Sea Dogs loaded the bases with one out in the third, but Duensing got Lowrie swinging on a full count, then departed in favor of Jesse Floyd, who was originally scheduled to start. Floyd whiffed catcher Dusty Brown on three pitches, and the Sea Dogs had stranded six runners through the first three innings. They finally got on the board with back-to-back two-out doubles by Bacani and Ellsbury in the fourth that made it 3-1.

“I’m just trying to drive the ball,” Ellsbury said. “I think last year I saw a lot of pitches and a lot of times I wasn’t ready to hit early in the count, just having that leadoff mentality. But the difference last year to this year is if I get a pitch early in the count to swing at, I’ll be ready and try to drive that ball.”

New Britain (1-1) broke it open in the sixth with four runs off reliever Scott Shoemaker in the sixth, including RBI hits from Hughes and Geiger. The bottom third of the Rock Cats order, Peterson, Hughes and Geiger, reached base six times and drove in six runs.

“They worked the count, and I think most of them hit in deep counts,” said New Britain manager Riccardo Ingram. “If the bottom of the lineup can get the pitcher to throw some pitches, that’s what you want.”

“It’s amazing what can happen with a little more concentration because of the cold weather,” he added. “You don’t want to hit that ball near the end of the barrel or get jammed, so you wait to get a good pitch.”

Portland got two back when Bacani went deep to left-center with one out. Ellsbury followed by turning on the jets and stretching a hit into short right into a double. But he was stranded for the third straight time in scoring position when reliever Jay Sawatski fanned cleanup hitter Keylor.

The Rock Cats tacked on a run in the seventh. Portland answered with a run in the bottom of the frame and finally pushed Ellsbury across after his third double on a Keylor single with two out in the eighth. Back-to-back walks by Lowrie and Dusty Brown made it 8-6 and put the tying run in scoring position. Reliever Tim Lahey squashed the rally by getting Andrew Pinckney to line out to third.

Floyd earned the win despite giving up three earned runs in three innings of relief, and Lahey collected the save with an inning-and-a-third of perfect relief. Hottovy (5 IP, three hits, three earned runs, two walks, three Ks) took the loss.