We’re well into the month of August now, and that means postseason races are heating up. With the stakes rising as we get ever closer to October, there are going to be a lot of big series to keep your eye on the rest of the way.

This week is packed with intriguing matchups between clubs in the thick of division and Wild Card races. A pair of surprise National League contenders face off, as do American League powers from the East and West. There's also an Interleague matchup between two of the hottest teams in baseball, each surging in the standings after a disappointing first half.

Here are five of them you want to be sure not to miss this week:

Marlins (58-55) at Reds (59-55)
3 games (Monday-Wednesday)

Head-to-head: The Reds took two of three games when the clubs met in Miami from May 12-14. Cincinnati won three of the four matchups between the teams in 2022.

Storyline: Both the Marlins and Reds were surprise teams in the first half of the season, with Miami heading into the All-Star break with a 53-39 record, and the Reds going into the break in first place in the National League Central with a 50-41 mark. But since then, both clubs have fallen on hard times. With a fourth consecutive loss Sunday against the Rangers in Texas, Miami fell to 5-16 in the second half. Meanwhile, Cincinnati has lost six straight and is 9-13 since the All-Star break.

Watch out for: Rookie right-hander Eury Pérez is returning to the mound for the Marlins after spending a month in the Minors to monitor his workload. The 20-year-old, who was MLB Pipeline’s top pitching prospect when he debuted with Miami on May 12, posted a 2.36 ERA in 11 starts -- that was the lowest ERA for a pitcher 20 years old or younger over his first 11 starts in the Live Ball Era (since 1920).

Giants (61-51) at Angels (56-57)
3 games (Monday-Wednesday)

Head-to-head: The Giants and Angels will be meeting for the first time since 2021, when San Francisco won three of the four games in the season series. The teams split a two-game set at Oracle Park from May 31-June 1, and then the Giants won both games of a two-game series at Angel Stadium from June 22-23.

Storyline: Both clubs are in need of a turnaround after disappointing performances over the weekend. The Giants dropped two games to the team with the worst record in baseball, the cross-bay A’s. Prior to that, San Francisco had won three consecutive series against the A’s, Red Sox and D-backs. The Angels, meanwhile, have been in freefall since the Trade Deadline, when they decided to hold on to impending free agent and two-way superstar Shohei Ohtani, losing six straight and teetering on the brink of falling out of postseason contention.

Watch out for: Ohtani is always someone to watch out for, but in this case, not only for his unparalleled two-way excellence. Ohtani, who is scheduled to start in the series finale against the Giants on Wednesday, has thrown 13 scoreless innings over his past two starts, but his last outing was cut short after four frames due to cramping in his pitching hand and fingers. In three games at the plate since then, he’s 2-for-12.

Padres (55-57) at Mariners (60-52)
2 games (Tuesday-Wednesday)

Head-to-head: These clubs split a two-game series at Petco Park from June 6-7. The Mariners won three of four in the season series last year.

Storyline: The Mariners have finally gotten on a roll after a lackluster first half for a club that had high hopes coming off their first postseason appearance in 21 years. Seattle just polished off a four-game sweep of the Angels in Anaheim and has won 10 of its last 12 overall. The Padres also had a disappointing first half of the season, and while San Diego’s second half hasn’t been as good as Seattle’s thus far, it’s been an improvement. Despite losing at Dodger Stadium on Sunday, the Padres have won seven of their last 11 to get back into the thick of the NL Wild Card chase.

Watch out for: If the Mariners are going to make a postseason push, they’ll need their superstar center fielder to deliver in big moments. And it appears Julio Rodríguez is starting to heat up at the plate. Over his past three games, J-Rod is 7-for-11 with three doubles and a homer. Watch for the engine that drives the M’s to propel them forward in their current hot stretch when they return home to host the Padres.

Astros (64-49) at Orioles (70-42)
3 games (Tuesday-Thursday)

Head-to-head: This will be the first head-to-head meeting of these American League powerhouses in 2023, and Tuesday’s opener will be the first of six games in the season series, with the other three scheduled for Sept. 18-20 at Minute Maid Park. The Orioles took the season series last year, four games to three.

Storyline: The Orioles have passed every test so far this season when it comes to proving their mettle as one of the best teams in baseball. Now they’ll welcome the defending World Series champions into town for three games between a pair of teams playing good baseball.

Baltimore is coming off a weekend sweep of the Mets, which came on the heels of series wins over the Blue Jays and Yankees. The Astros just split a four-game set in the Bronx after sweeping the Guardians at home. The first-place O’s look to put some more distance between themselves and the Rays in the AL East, while the Astros try to close the 2 1/2-game gap between themselves and the Rangers in the AL West.

Watch out for: Framber Valdez will take the mound for the first time since throwing a no-hitter against the Guardians last Tuesday. The historic feat came following a series of rough outings for the star left-hander -- over his previous three starts, he gave up 15 runs in 15 innings. Keep an eye on Valdez to see if the no-no gets him going in the right direction down the stretch for Houston.

Cubs (58-54) at Blue Jays (63-50)
3 games (Friday-Sunday)

Head-to-head: This will be the first meeting between the Cubs and Jays since Toronto won two of three at Rogers Centre from Aug. 29-31, 2022. Prior to that series, the clubs hadn’t met since 2017. 

Storyline: Both teams are playing well of late and trying to make a strong postseason push as we hit the stretch run of the regular season. The Cubs have been red-hot, winning 15 of their last 19 games to vault themselves back into contention in the NL Central. That includes an impressive series win over the weekend against the Braves. The Blue Jays are coming off an emphatic sweep of the Red Sox in Boston, winning the series finale Sunday by a 13-1 margin. Toronto looks to gain a tighter grip of its hold on an AL Wild Card spot.

Watch out for: Davis Schneider, the Blue Jays’ No. 28 prospect per MLB Pipeline, had a debut series for the ages in Boston over the weekend, becoming the first player in MLB history to pick up nine hits, including two home runs, over the first three games of his big league career. Schneider was the catalyst that sparked a Toronto offense that had been dormant following Bo Bichette’s knee injury. Schneider will be appointment viewing during this series.