Both teams need each game of their regular-season-ending three-game series, which starts on Monday night at Tropicana Field.
The Rays' position is much more precarious. Even after beating the White Sox on Sunday for their 10th victory in 11 games, they trailed the A's by three games for the final AL Wild Card spot, with Oakland beating Seattle. Tampa Bay is also tied with the Angels, who are also on the verge of elimiation.
The Orioles clinched their first postseason berth since 1997 after defeating the Red Sox on Sunday for their fourth consecutive win and 11th out of 14, coupled with the Angels' loss to Texas in the second game of their day-night doubleheader.
The Orioles remain tied with the Yankees for the AL East lead. New York will host Boston in its final series.
Monday's series opener will pit the Orioles' Wei-Yin Chen against the Rays' Alex Cobb, as Baltimore seeks to extend its winning streak over Tampa Bay to six.
Chen hasn't won since Aug. 19 and is 0-3 with a 5.90 ERA in five September outings. The 27-year-old rookie from Taiwan will be pitching on six days' rest after giving up five runs in five innings against the Blue Jays in his previous start.
"After the first batter in the first inning, I walked a guy. I started feeling like, 'Wow. This is not the day for me,'" Chen said afterward through an interpreter. "I tried to fight, fight through it. It definitely was not my day, things went a different direction."
Cobb has bounced back from an eight-run outing on Aug. 18 by posting a 2.72 ERA in six starts since. He held the Red Sox to one run over five innings on Wednesday.
"I mean, it's been up and down all year," Cobb said. "It's been good of late. I'd say after the All-Star break, it started getting a lot better. I started feeling more comfortable. Before that, it was more of a fight and just trying to battle. But it's been a lot smoother down the stretch."
The 24-year-old has thrown a career-high 170 2/3 innings between Triple-A Durham and Tampa Bay, but said he feels good despite pitching this late in the season for the first time.
"There's some days that I do feel tired," Cobb said. "But when game day comes, there's so much adrenaline that your body feels fine and everything is good to go. But in between days, I'm a little bit tired."
Orioles: Jones team MVP once again
Center fielder Adam Jones has become the seventh player in team history to win back-to-back team Louis M. Hatter Most Valuable Oriole Awards, an honor voted on by members of the local media who cover the team regularly. The last to do it was Rafael Palmeiro in 1995-96.
After going 1-for-4 on Sunday, Jones is hitting .288 with an .846 OPS and a career-high 32 home runs. He also has 103 runs scored, 81 RBIs and 16 stolen bases.
Second baseman Brian Roberts, who lives in Sarasota, Fla., is expected to join the Orioles for the series. Roberts played in 17 games, the last coming on July 1, before having season-ending hip surgery.
Rays: Rodney making history
With his scoreless ninth inning to close out Sunday's win, Fernando Rodney tied Hall of Famer Dennis Eckersley's Major League record for lowest ERA by a reliever, in a season with at least 50 innings.
Rodney has held the opposition to five earned runs in 73 1/3 innings, the exact same numbers Eckersley posted in 1990, good for a 0.61 ERA. That means Rodney needs at least one-third of a scoreless inning to have the record to himself.
Two other members of the Rays' bullpen, Wade Davis and Jake McGee, have combined to strike out 50 of the 101 batters they have faced in their last 30 1/3 innings.
The Orioles lead the season series with the Rays, 9-6, although the teams have split their six contests at Tropicana Field.
Chen has a 3.38 ERA in four starts against the Rays, including a 3.55 mark in two road outings. Cobb gave up two runs in 4 2/3 innings in his lone start against the Orioles, on Sept. 12 at Camden Yards.