As a HUGE baseball fan myself I got to go to a Red Sox game about 5 years ago. FYI try and get the tickets beforehand - literally find out when they go on sale for the season and get on the internet and try and get yourself the necessary number of tickets. Otherwise....
...unless its changed, you will then have to line up outside the stadium with about 4 - 500 hundred other individuals to try and get game day tickets. We were first in line but we actually waited some ridiculous amount of time - something like 5 or so hours beforehand. It's absolutely ridiculous. I think they technically have a rule about how soon you can line up as well, so you may have to be "around" just not technically in line. Also, not sure how often its enforced, but technically everyone going to the game has to be in line - i.e. you can't have your buddies go off and drink and you each take a turn in line. If I remember correctly, at a random time, some staff member(s) from the Red Sox will come out and give the people in line a piece of paper or something that says they are in line/can get a ticket. Doesn't reserve your spot in line, but I think technically it allows you to buy a ticket - and they will only give one to each person literally there. So if you are standing in line, but buddies are not there, you would only get 1 piece of paper thingie...which theoretically means you could only buy 1 ticket. Not so much fun.
Long story short: try and buy your tickets online. I would even phone the Red Sox now, explain your situation and see if they can do anything or provide suggestions. We had multiple people try to bribe our spot in line...even people that would somehow be offering a ticket to the game, yet want to take over your spot in the line up. Hmmmm
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