Behind home runs from Torii Hunter, Vernon Wells and Chris Iannetta, the Angels cruised to an 8-3 win on Monday, giving them 10 victories over their past 13 games and stopping the A's winning streak at nine. The Halos are 3 1/2 games behind the Orioles for the second American League Wild Card spot and 4 1/2 back of the A's for the first spot.
"It's going to be a good test for us, no doubt," the Angels' Mark Trumbo said. "We don't have a ton of time left. It's up to us to go in there and take care of business, but I don't think we can ask to be in a better spot than the last couple of series that we've played."
After their trip to Oakland, the Angels will head home for another important three-game series over the weekend against the Tigers, who are also in a tight race with the White Sox for the top spot in the AL Central.
However, this week's games could have the most impact on the AL East, with the Yankees finishing out their three-game set against the Rays at Tropicana Field before traveling to Baltimore for a four-game set.
While the Yankees have been in sole possession of first place for 83 consecutive days, that number is getting tighter with each passing day. Losers in nine of their past 13 games, the Yanks did get a boost on Monday with the return of Alex Rodriguez to the lineup. Rodriguez hadn't played with the team since having his left hand fractured by a Felix Hernandez pitch on July 24 in Seattle.
Yet, A-Rod's presence in the lineup didn't prevent New York from dropping a 4-3 decision to Tampa Bay. With the Orioles picking up a 4-0 win over the Blue Jays, Baltimore moved within a game of the Yankees. The win also put the Rays just 1 1/2 games back in the Wild Card and 2 1/2 in the division.
"It's now September. It's time to go, it's time to win," Tampa Bay's James Shields said. "Definitely going to be a big series. This is one of two series we're going to be playing against them in the next month, and yeah, it is huge."
Another test will come for the Rays later in the week, when the Rangers visit the team for a three-game series. Tampa Bay lost two of three games to Texas at the end of August in Arlington.
In the Senior Circuit, a pivotal three-game series that begins Friday between the Dodgers and Giants in San Francisco could decide the National League West. Los Angeles will hope for a better outcome this time around after being swept by San Francisco in three games at Chavez Ravine from Aug. 20-22.
The Giants currently hold a 4 1/2-game lead over the Dodgers going into Tuesday's games. On Monday, San Francisco got a 9-8 win against Arizona in 10 innings, while Los Angeles also got a victory in extras, beating San Diego, 4-3, in 11 innings. The win also moved the Dodgers a half-game back of the second NL Wild Card spot.
"I think we know where we are at. We are capable, and that is a good feeling to know that," Dodgers manager Don Mattingly said. "We are capable of rattling some games off. I've been around just long enough to know that two days from now, three days from now, we can be on a roll, and all of a sudden we don't think we can be beat."
While the other NL divisional races aren't as close, the Reds will look to pad their current 8 1/2-game lead against the Astros in Cincinnati beginning Friday, just as the Nats face the Marlins in Washington and try to increase their 6 1/2-game lead over the Braves.