The 2013 Major League Baseball season started on March 31 with a Sunday night game between the Texas Rangers and the Houston Astros.^[1] Opening Day for most clubs was a day later on April 1. The regular season ended on September 30, extended one day for a one-game playoff between the Tampa Bay Rays and the Texas Rangers to decide the second American League Wild Card winner.
The 2013 season was the first with the Houston Astros as a member of the American League (AL) in the West Division. This marks the first growth in the number of American League teams since the 1977 Major League Baseball expansion added the Seattle Mariners and Toronto Blue Jays. When the then-named Tampa Bay Devil Rays were added to the AL in 1998, the Milwaukee Brewers were reassigned to the National League (NL) the same year, keeping the AL at 14 teams. Owing to the Astros' league switch, both leagues have fifteen teams, necessitating inter-league games to be played throughout the entire season for the first time in MLB history.
The Major League Baseball All-Star Game's 84th edition was held on July 16 at Citi Field in Queens, New York City, home of the New York Mets with the American League winning the All-Star Game with a 3–0 shutout of the National League. With the win, the American League champion earned home field advantage for the 2013 World Series. Taken from https://en.wikipedia.org/wiki/2013_Major_League_Baseball_season

Final Stats:

MLB Detailed Standings
Rk	Tm	Lg	G	W	L	W-L% ▾
1	BOS	AL	162	97	65	0.599
2	STL	NL	162	97	65	0.599
3	OAK	AL	162	96	66	0.593
4	ATL	NL	162	96	66	0.593
5	PIT	NL	162	94	68	0.58
6	DET	AL	162	93	69	0.574
7	CLE	AL	162	92	70	0.568
8	LAD	NL	162	92	70	0.568
9	TBR	AL	163	92	71	0.564
10	TEX	AL	163	91	72	0.558
11	CIN	NL	162	90	72	0.556
12	WSN	NL	162	86	76	0.531
13	KCR	AL	162	86	76	0.531
14	BAL	AL	162	85	77	0.525
15	NYY	AL	162	85	77	0.525
16	ARI	NL	162	81	81	0.5
17	LAA	AL	162	78	84	0.481
18	SFG	NL	162	76	86	0.469
19	SDP	NL	162	76	86	0.469
20	TOR	AL	162	74	88	0.457
21	COL	NL	162	74	88	0.457
22	MIL	NL	162	74	88	0.457
23	NYM	NL	162	74	88	0.457
24	PHI	NL	162	73	89	0.451
25	SEA	AL	162	71	91	0.438
26	MIN	AL	162	66	96	0.407
27	CHC	NL	162	66	96	0.407
28	CHW	AL	162	63	99	0.389
29	MIA	NL	162	62	100	0.383
30	HOU	AL	162	51	111	0.315
Postseason
WorldSeries (4-2):	Boston Red Sox over St. Louis Cardinals
ALCS (4-2):	Boston Red Sox over Detroit Tigers
NLCS (4-2):	St. Louis Cardinals over Los Angeles Dodgers
LDS (3-1):	Boston Red Sox over Tampa Bay Rays
LDS (3-2):	Detroit Tigers over Oakland Athletics
LDS (3-2):	St. Louis Cardinals over Pittsburgh Pirates
LDS (3-1):	Los Angeles Dodgers over Atlanta Braves
WildCardGame (1-0):	Tampa Bay Rays over Cleveland Indians
WildCardGame (1-0):	Pittsburgh Pirates over Cincinnati Reds
Most runs per game: 5.3
BOS
Fewest runs allowed per game: 3.4
ATL
Boston Red Sox final stats:
Most runs scored in a game: 20
Wednesday, Sep 4	boxscore	BOS		DET	W	20	4
Most runs allowed in a game: 15
Wednesday, May 8	boxscore	BOS		MIN	L	8	15
Longest game by time: 5:24
Monday, Jun 10	boxscore	BOS	@	TBR	W	10	8	14 innings