NEW YORK -- As fans return to major league stadiums for openers Thursday amid pandemic attendance restrictions in most places, baseball commissioner Rob Manfred can envision filled ballparks by midseason.

Capacity will be limited to about 12% at the season's start in Boston and Washington. Twelve teams are at 20%, Colorado at about 43% and Houston at 50%. The only team higher is Texas, which is at 100%.

"I hope by midsummer that we have ballparks that are unrestricted and we have full fan access," Manfred told The Associated Press on Wednesday.

Last year's shortened regular season was played entirely without fans, who were allowed back only for the National League Championship Series and World Series in limited numbers for games moved to a neutral site in Arlington, Texas.

"For most clubs, this will be another year of significant losses. It's not going to be the $2.5 [billion] to $3 billion that we had last year, but there will be significant losses if we continue in the mode where we don't have full fans," Manfred said. "The clubs have done a great job of working with financial institutions they had relationships with in terms of assuring liquidity."

Manfred said he thinks most players could be vaccinated against COVID-19 by mid-May. The St. Louis Cardinals and Astros said Monday that their players will be offered vaccines before openers, and the San Francisco Giants said some of their players already had received shots.

"I am pleased that we have gotten here," Manfred said. "I think the players and the club people did a tremendous job during spring training, a continuation of what they did last year. And I'm just hopeful we're going to be able to play a season that looks like normal."

He said he thinks fans long to return to ballparks.

"I see this season as a huge opportunity for baseball," Manfred said. "We're an outdoor sport. I think it's safe or safer to go to outdoor activities. Everybody seems to agree on that. And I think that there's pent-up demand for entertainment products, and we're going to do everything we possibly can to take the best opportunity to take advantage of that."

In separate interviews with the AP, Manfred and union head Tony Clark said they have started discussing the possibility of moving the All-Star Game from Atlanta in July over concern about legislation adopted in Georgia restricting voting rights.

"He wanted to have a conversation. I completely understand why Tony would want to have a conversation about this topic. We've actually had a preliminary kind of conversation, and there will be more substantive conversations about that," Manfred said. "I am talking to various constituencies within the game, and I'm just not going beyond that in terms of what I would consider or not consider."

Manfred expects a series of announcements this summer on All-Star sites for 2023 to 2025. Los Angeles will host in 2022 after the coronavirus pandemic caused the cancellation of last year's All-Star Game at Dodger Stadium.