BRADENTON, Fla. -- The Pirates are not saying so, but it is becoming abundantly evident Zach Duke will start opening day.

The team has begun rotating starters on five-day schedules, and Duke's first spin in that sequence will be today against the Tampa Bay Devil Rays at McKechnie Field. If he stays on that schedule -- factoring in the team's day off Tuesday -- he is in line to pitch the opener April 3 in Milwaukee.

Moreover, the only other realistic candidate, Oliver Perez, barely has been on the mound this spring. He has pitched two innings March 1 against Manatee Community College and one inning for Mexico at the World Baseball Classic.

Duke, who has a 5.40 ERA in two appearances this spring, is adamant the opener has not entered into his thinking.

"I don't know if they've set it up that way or not," he said yesterday. "I'm just throwing to get ready. If I hear something ... "

Duke started opening day last year, too, only it was with Class AAA Indianapolis. He won by limiting Pawtucket to three runs in five innings.

Duffy beaned

Chris Duffy had a mild concussion after being beaned in the Pirates' 10-7 victory against the Boston Red Sox yesterday at McKechnie Field. His official status is day to day.

Duffy led off the fourth inning when an 0-2 fastball from Boston ace Curt Schilling cracked the right side of his helmet. Duffy was not felled, but manager Jim Tracy removed him immediately. A team physician took him to a hospital for a CT scan.

Schilling, who has told reporters he wants to pitch inside more for the first time in his career, beaned a teammate in an intrasquad scrimmage last week.

Schilling placed partial blame on Duffy, saying, "He should have been able to get out of the way of that pitch."

Tracy disagreed with that, but he absolved Schilling.

"I don't think Curt Schilling goes out there to hurt people," Tracy said. "Period.'

It marked the second time in four days one of the Pirates was beaned. Sean Casey played his first game yesterday since being plunked Wednesday by the Cincinnati Reds' Michael Gosling.

Other game highlights

Ryan Vogelsong gave up four runs in three innings. He pitched behind most of the time -- 25 balls among 59 pitches -- and gave up six hits and a walk. He has a 6.22 ERA, and opponents are batting .351.

Through three innings, Schilling silenced the Pirates' strongest lineup of the spring -- six of eight projected starters -- as Boston took a 4-0 lead. But he allowed four runs in the fourth, one scoring on a Jeromy Burnitz double.

Freddy Sanchez went 2 for 3 with three RBIs, including a two-run double in the sixth that gave the Pirates an 8-7 lead.

Buried treasure

The lineup offered clues as to how Tracy might shape the heart of his order: Casey continued to bat third, Craig Wilson was at cleanup while taking Jason Bay's place in left field, and Burnitz was fifth. If Casey and Burnitz remain in those spots, Bay is sure to bat cleanup and, in turn, fulfill Tracy's wish to alternate left- and right-handed hitters.

Bay and infielder Yurendell DeCaster returned to Bradenton after their teams were eliminated in the Classic.

The Devil Rays will start Casey Fossum today.