OAKLAND – One adjustment that A's infielder Eric Sogard made over the offseason – slightly bigger lenses, tortoiseshell frames.

The rare position player who wears prescription eyeglasses on the field, Sogard said he decided to try a new brand this winter. He said the lenses help his peripheral vision and the frames are comfortable, which is the most important thing. The design was the most flattering of the pairs he tried on, he said, "according to my wife."

"And they've been seeing the ball all right," Sogard said.

That is, Sogard's been seeing the ball all right through them virtually all spring. He ended Cactus League play with a .444 average. On Saturday, Sogard learned he will be on the A's 25-man roster when they open the season Monday against the Seattle Mariners.

The A's announced their Opening Day roster shortly after beating the Giants 4-3 in each team's final exhibition game. Uncertainty had remained only in the middle infield and over the final bullpen spot, which went to right-hander Evan Scribner.

Shortstop Hiroyuki Nakajima (hamstring) was placed on the 15-day disabled list to start the season retroactive to March 27. Jed Lowrie will likely start out as the A's shortstop, with Sogard and Scott Sizemore sharing time at second base.

First baseman Nate Frei-man, whom the A's claimed off waivers from the Astros on March 23, also made the roster and will be a right-handed complement to Brandon Moss.

Sogard broke camp with the A's last year as well but came in this season as a long shot. He struggled in 37 games with the A's as a utility player in 2012, batting .167, and spent time in Triple A and on the disabled list.

This spring, his prospects appeared impeded by the acquisitions of Nakajima and Lowrie and Sizemore's return from injury.

The middle infield picture began to clear last week with Nakajima's injury and Adam Rosales going to the DL with a strained left rib-cage muscle.

But Sogard was already opening eyes himself, hardly going a Cactus League day without a hit.

"In the past in the big leagues it's been hard for me to get into a rhythm at the plate playing once every four or five days," Sogard said. "That's just the kind of player I am.

"I understand I may not be in there every single day, but hopefully I can be in there and just stay relaxed because I've had experience doing it in the past. … I'm not trying to get too hyped up and do too much. Just staying relaxed and having fun with it."

Nakajima, meanwhile, said he is disappointed to be starting the season on the DL but understands the A's want to make sure he recovers fully from a left hamstring strain. Manager Bob Melvin said when Nakajima is healthy he'll likely head to the Triple-A River Cats for a rehab assignment, which Nakajima said he would welcome.

That move opened a spot for Freiman, whom the A's would have had to expose to waivers had he not made the 25-man roster. The 6-foot-8 Freiman, who has not played above Double A, said he "may have been shaking" when Melvin told him before batting practice.

"Probably still shaking a little bit," Freiman said after the game.

Scribner beat out left-hander Pedro Figueroa and nonroster invitees Mike Ekstrom and Hideki Okajima for the final bullpen spot. The A's optioned Figueroa and infielder Andy Parrino to Triple A, and reassigned Ekstrom and Okajima to minor-league camp along with catcher Luke Montz.

Melvin said the bullpen decision was difficult because several candidates – including Jordan Norberto and Travis Blackley, who were optioned and designated for assignment, respectively, on Friday – contributed to last year's division title.

"But they also understand that we make some moves around here," Melvin said of the trimmed relievers. "If someone's pitching well and doing well and someone's not, we'll flip it out in a hurry. So they know they have to stay on top of it."

Call The Bee's Matt Kawahara, (916) 321-1015. Read his Bay Area Baseball blog at blogs.sacbee.com/bay-area-baseball/. Follow him on Twitter @matthewkawahara.

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