This may be the liquor store closest to Fenway Park, steer clear on game days.

Boston Billiards was hailed “the hands-down finest room in the country” by Billiards Digest, and it's easy to see why, with the club's 32 ft. long mahogany bar, dark wood accents, classy lighting, and cushy leather lounge. Most people come for the 50 billiard tables, but basic foods (most $5-8), 20 different beers (8 on tap, including $2 Miller Lite), a lengthy cocktail menu, and an arcade provide other welcome distractions. The clientele ranges from college kids to senior citizens, though suits are plentiful during happy hour. Free parking after 6pm except when there's a Sox game. Tables: before 5pm M-F $8/hr, Sa-Su $10/hr; after 5pm Su-Th $11/hr, F-Sa $13/hr. $2/additional player over 2 players. Free lessons M 7:30pm. W ladies night: 25% off for each woman when up to 3 playing, or free for 4 per table.
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Great comfort food and slow roasted bbq and ribs. It even has it's own parking lot in the Fenway area. This locale not only serves up heart food and BBQ, it has a large proch for outdoor dining, live music, and free parking. It does not take a genius to know that is hard to come by in Boston.

Copperfield's, located on Brookline Ave just a stone's throw from Fenway Park, is a great alternative to the more popular Game On! and Cask and Flagon. The ambiance of Copperfield's may not stand up to its more polished competitors, but where Copperfield's lacks in aesthetic charm it compensates for in great service. While your buddies are vying for a barstool before or after a Sox game, you can show them how savvy you are by easily snagging a comfortable seat (and several beers) at Copperfield's. They might not be impressed with the dungeon-like decor, but they'll certainly be glad that you've found someplace to drink that doesn't involve battling tourist and fans for a place to stand.
If you're looking for a quick bite to eat and some passable pub grub Copperfield's isn't your place. This bar only serves beverages.
Open weekdays from Noon-2am. Hours vary on game days.

This is the local "packy" (package store) for the folks on Queensberry and Jersey Streets. Jersey Street Liquors is pretty standard as beer, wine, and liquor selection goes. If you're looking for any spirit that might be considered hard to find, you can bet that this location won't have it.
That being said, that doesn't mean that Jersey Street liquors is inadequate. The location is small, clean, and incredibly convenient if you live in the Queensbury/Peterborough area.

This sports bar sits just on the edge of Fenway Park. If you can't get tickets to the game, you can watch it from the roof deck here with it's mini version of the Green Monster and feel like your as close as you can get. It's got your classic bar food menu (wings, burgers, beers) and a friendly atmosphere. A great place to watch the game for the more traditional Fenway bar experience. The crowd here is generally a bit older than at Game On.

Boston Beer Works is the oldest brewery/restaurant combo in Boston. They have 3 locations, this one across from Fenway is bustling during baseball season and throughout the year. The beers on tap change weekly. Usually there are several seasonal offerings to go along with a stable of beers, ranging from light to dark. There are alternatives for those not inclined towards the hop-laden brews too. The food is excellent - basic American bar food done right. And what's better than tucking into a burger and a beer? Chowing down right next to the tanks where that beer was made.

A famous watering hole, often featured in live camera shots during crucial Red Sox games. The Cask 'n Flagon is where Red Sox nation gathers to celebrate or commiserate. Recently featured in the Reebok ad that debuted during the 2007 World Series - Donny Wahlberg sat at the bar here, and Bobby Orr walked by too. Those heading to a game can save a few bucks by filling up on the Cask's straightforward bar fare and skipping the ballpark's expensive snacks. The walls are lined with high-definition TVs and photos that depict the histories of Fenway and the Sox. Locals fill the huge wraparound bar that resides in the middle of the main room while keeping an eye on all the sports news via an ever-present sports ticker. The Cask has some of the city's most aggressive bouncers--be on your best behavior.

A bar on the edge of Fenway Park's outfield. You enter from Lansdowne Street, but a large window in the sitting area allows diners and drinkers to peer out onto the field to watch the games. According to BU Today, there's "no nachos, no chicken wings, no quesadillas," so don't expect typical bar fair; "high-end," classic sandwiches like "pastrami, salami, beef brisket, corned beef, liverwurst.... turkey club, grilled cheese with bacon, and 'sliders'" make up the better part of the menu's hearty choices. Click here to view their menu. On tap: Bud, Miller Light and Sam Seasonal.