The 2023 schedule features more different matchups than ever before as each team plays each other team over the course of the season. Some of these unique series pop up this week, including a pair of Interleague matchups between first-place squads. Here are five series to watch during the week of May 15:

Angels (21-20) at Orioles (26-14)
4 games (Monday-Thursday)

Head-to-head: The Orioles dominated the series in 2022, taking eight of nine games against the Angels. Both teams are improved so far this season, though. Baltimore currently has the second-best record in the American League while Los Angeles is one game above .500 after finishing 16 games below last season.

Storyline: The Orioles' hot start. If it wasn't for the Tampa Bay Rays, who are making MLB history with their start to the season, this young Baltimore team would be the talk of baseball. The Orioles were looked at by most as one year away from truly competing in the tough AL East. It looks like they've arrived early.

Watch out for: Everyone knows about what Shohei Ohtani and Mike Trout are doing. But take a look at the year Hunter Renfroe is having. Renfroe has 10 home runs so far this season, which is tied for the eighth-most in the Majors. The Angels added Renfroe hoping that he would provide some protection for Trout and Ohtani in their lineup. He's done that and then some.

Braves (25-15) at Rangers (25-15)
3 games (Monday-Wednesday)

Head-to-head: The Braves and Rangers matched up last season for the first time since the 2017 season. Texas took two out of three during that series despite Atlanta being the much better team in 2022. That's changed this season -- both teams lead their division by a healthy margin.

Storyline: Are the Rangers for real? After a big offseason that brought in Jacob deGrom, Nathan Eovaldi, Andrew Heaney and a new manager in Bruce Bochy, Texas fans expected an improvement on 2022. But this good? A solid showing against this excellent Braves team could help prove to doubters that the Rangers are here to stay.

Watch out for: Ronald Acuña Jr., who is perhaps the leading NL MVP candidate at this point in the season. After tearing his ACL in July 2021, Acuña didn't quite look like himself last season. He's definitely back to being himself now. Acuña is second the National League in batting average (.346) and stolen bases (17) all while flashing his pre-injury power (8 home runs).

• 6 reasons Rangers are off to historic start

Twins (23-18) at Dodgers (26-15)
3 games (Monday-Wednesday)

Head-to-head: Like the Braves and Rangers, the Twins and Dodgers haven't played much in recent seasons. But when they have, Los Angeles has stolen the show. Going back to 2011, the Dodgers have won each of their last 10 games against the Twins.

Storyline: Carlos Correa's struggles. After a roller-coaster offseason, Correa ended back up in Minnesota, but the season hasn't started as planned for the star shortstop. Correa is hitting just .200 with a .676 OPS and a 87 wRC+. Correa has been vocal about his frustrations. Is this the series he turns it around?

Watch out for: Will Smith. Thanks to a concussion that cost him about two weeks of playing time, Smith's counting stats aren't the flashiest, but he's the Dodgers' most valuable player when he's on the field. Smith is slashing .322/.417/.598 with a 172 wRC+, filling the shoes of Trea Turner and Justin Turner in LA's lineup from the catching position.

Rays (31-11) at Mets (20-21)
3 games (Tuesday-Thursday)

Head-to-head: The Rays have won five out of six games against the Mets since 2020, but both series came before New York became the big-market juggernaut they are today. The Mets have struggled while dealing with injuries so far this season, but don't be surprised if these are the last two teams standing in October.

Storyline: Tampa Bay's historic start. They already hold a four-game lead in the AL East -- a division packed with potential playoff teams. There's a lot of season left, but the Rays are on pace to be one of the very best teams of all time.

Watch out for: New York's starting pitching. It's been ... not great. The starting pitchers' 5.38 ERA so far this season is eighth-worst in the league. Now, the Mets have had their fair share of injuries -- Max Scherzer, Justin Verlander and Carlos Carrasco have all missed time. But if they want to compete in the NL East, their starting unit must improve.

Red Sox (22-19) at Padres (19-22)
3 games (Friday-Sunday)

Head-to-head: The Red Sox have had all the fun versus the Padres over the past decade, going 7-2 in nine contests, but these are two very different-looking teams since the last time they met in 2019.

Storyline: The Xander Bogaerts and Red Sox reunion. Bogaerts played the first 10 years of his career in Boston before joining San Diego this past offseason.

Watch out for: Juan Soto. He's coming out of his slump. Soto has gone off over the last two weeks, averaging .370/.473/.696 since the calendar turned to May.