We’re going to hear plenty of relief pitchers mentioned as potential trade candidates in the coming weeks, though 23 of the league’s 30 clubs entered this week within 5 1/2 games of a postseason spot, so we might not know which teams will prove to be sellers by Aug. 1.

What we do know is that most -- if not all -- contending teams are on the lookout for relief help. Pitchers are traditionally more coveted than position players around the Trade Deadline, mainly because pitching casts a much wider net.

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If a first baseman is made available by a non-contender, for example, most winning teams are likely to already have an established player at that position. But pitching is different -- there’s always room to squeeze in another starter, and everyone can find a spot for a hard-throwing reliever.

What we also know is that most relievers whose names will pop up in trade talks fit into one of three buckets. Let’s take a look at three types of relief arms that teams will be looking at during the next seven weeks:

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The young fireballer

OK, so this category isn’t loaded with names, but there is one who could be one of the most fascinating relievers we’ll be talking about this trade season: Alexis Díaz.

Now, before Reds fans out there start screaming at their screen, let’s acknowledge that Cincinnati entered the week just four games back in the National League Central and three games out of a Wild Card spot. The Reds could wind up being buyers before all is said and done, but if we get toward the end of July and things have moved in the opposite direction, teams will surely be calling about Díaz.

The 26-year-old is striking out more than 16 batters per nine innings this season, converting all 15 of his save opportunities while posting a 1.71 ERA in his first 27 outings. Díaz won’t be eligible for arbitration until 2025, meaning he’s under club control through the end of the 2027 season.

So why would the Reds even think about trading him?

First, relievers tend to be more volatile than any other position in the game. Díaz could embark on a decade-long run of dominance, but we’ve seen enough examples of stud relievers struggling in their second or third season as the league adjusts to them.

More importantly, the return for a hard-throwing reliever with four-plus years of control can be too good to pass up. Díaz’s brother, Edwin, had an All-Star season for the Mariners in 2018, earning AL Cy Young and MVP votes in the process. That winter, he was dealt to the Mets with four years of control.

Granted, the Mariners’ deal also included Robinson Canó, so the comparison isn’t exactly apples to apples, but if the Reds can bring back a haul of prospects -- or possibly a Major League-ready answer at another position -- in exchange for Díaz, it’s not out of the question that something could come together.

The impending free agent

The most common type of reliever moved prior to the Trade Deadline, these pitchers on expiring contracts are popular targets for bullpen-needy clubs. As two- to three-month rentals, most of these relievers won’t require a hefty price tag, though the number of teams competing for those arms can sometimes make them costly.

Think back to 2016, when the Yankees were able to acquire a four-player package from the Cubs headlined by Gleyber Torres for Aroldis Chapman, the arm Theo Epstein believed was the final piece to a championship puzzle for Chicago.

Ironically, Chapman is among the group of potential rentals this summer, having signed a one-year, $3.75 million deal with the Royals in January. Chapman has bounced back from a tough 2022, posting a 2.82 ERA with 38 strikeouts in his first 24 appearances (22 1/3 innings) this season.

Other potential rental relievers: Carl Edwards Jr., Buck Farmer, Amir Garrett, Pierce Johnson, Joe Kelly, Craig Kimbrel, Reynaldo López, Trevor May, Keynan Middleton, Chasen Shreve, Brent Suter

The controllable asset

Unlike the impending free agents, this group of relievers offers at least one more year of club control, providing some bullpen stability beyond the 2023 season.

Just last year, the Brewers sent All-Star closer Josh Hader to the Padres in exchange for four players, a deal that put the left-hander in San Diego’s control through the end of 2023.

Two intriguing candidates in this category include right-handers Scott Barlow of the Royals and Kendall Graveman of the White Sox, who are both slated to become free agents at the end of the 2024 season. Both pitchers have closing experience but would slot in nicely in the setup mix with a contender.

Rockies closer Daniel Bard could also fit this description, as the soon-to-be 38-year-old is posting another phenomenal season after recording 34 saves and a 1.79 ERA in 2022. Bard, who is due $9.5 million in 2024, has a 0.96 ERA in his first 18 appearances this season.

Other potential one-plus relievers: Kyle Finnegan (arbitration-eligible for two more seasons), Jason Foley (under control through 2027), Brad Hand ($7 million team option for 2024), Hunter Harvey (arbitration-eligible for two more seasons), Alex Lange (under control through 2027)