The Overwatch League's hero pools will be in effect for the first time this weekend and Reinhardt, Moira, McCree, and Widowmaker are on the chopping block. It's difficult to gauge exactly what effect these bans will have on this weekend's upcoming matches in Washington DC, but here's a quick look at the bans and how they could potentially shake up compositions in the league.

Support Ban: Moira -- 12 percent pick rate over the first four weeks (ninth most-used hero overall)

Moira was an unexpected hero pools ban -- most teams stuck with a tried-and-tested Ana-Lúcio support line for their healing needs. Blizzard

Of all supports that were used heavily in the first month of league play, Moira was significantly behind Ana (fifth most-used of all heroes at 76 percent) and Lúcio (second most-used of all heroes at 87.9 percent).

Ana and Lúcio were considered to be shoo-ins for this first ban, but Moira was also eligible by breaking the 10% pick rate threshold. Moira being taken off the table has a significantly lower impact on overall play and compositions that we've seen from teams thus far. In fact, three teams of the 15 that have played -- the New York Excelsior, Florida Mayhem, and San Francisco Shock -- have not used Moira in their matches. The support line for the majority of teams in the league will be able to stay at an Ana-Lúcio combination, although I'm not ruling out other supports creeping in as the DPS and tank bans have a more significant effect on changing overall compositions.

In the first four weeks, the Paris Eternal favored Moira the most. Both Eternal flex supports, Damien "HyP" Souville and Luís "Greyy" Perestrelo, came in as the league's top two Moira players based on percentage picked at 26.4 percent and 55.6 percent. If any team this weekend will be affected by this, it's likely to be Paris, although they'll probably default to Ana or Brigitte based on current data.

Tank Ban: Reinhardt -- 89.4 percent pick rate over the first four weeks (most used hero overall)

Teams will have to do without Reinhardt in the first hero pools bans. Provided by Blizzard.

Although Moira was more on the periphery of the league's most popular picks, Reinhardt was decidedly not. As the most-used hero in the 2020 season to date, Reinhardt was expected to be part of the first ban rotation. Teams have commonly used Reinhardt alongside D.Va as a flex tank -- D.Va currently ranks as the fourth most-picked hero at 84.3 percent -- or in a double main-tank option with Reinhardt-Orisa.

When we look at Overwatch compositions from a distance, our eyes tend to go immediately to the DPS line. However, this Reinhardt ban is likely to have the most impact on overall compositions, given that the other main tank options in Orisa and Winston (or Wrecking Ball for that matter) play differently and bring wholly different things to a composition. Reinhardt hasn't just dominated the pick rate this year, but was also a crucial pick during the GOATs (triple tank-triple support) meta that dominated 2019. Combined with two hitscan bans in the DPS role and retaining Ana as a flex support, this could herald the return of dive compositions around Winston for the first time since Season 1. This means that main tanks like Atlanta Reign's Park "Pokpo" Hyeon-joon and NYXL's Kim "Mano" Dong-gyu might be allowed to flex their Winston muscles

DPS Ban: McCree -- 54.1 percent pick rate over the first four weeks (sixth most-used hero overall)

Widowmaker -- 11.7 percent pick rate over the first four weeks (10th most-used hero overall)

A good Widowmaker player can prevent many other DPS heroes from seeing playtime ... but she'll be unavailable due to hero pools. Provided by Blizzard

Across the first four weeks of the 2020 season, Mei has been the most-picked DPS hero by a significant margin. Third overall with an 85.6 percent pick rate, she's been the centerpiece for a number of different compositions that have used her excellent zone control and area of effect to set up their hitscan players on McCree and Widowmaker.

Mei is still around for Week 5, but both McCree and Widowmaker are not, leaving many wondering if teams will move away from the Mei and focus on more dive-oriented compositions, especially with Reinhardt off the table as well. The Mei-Reaper DPS combination is still available to teams like the Toronto Defiant, who could still look fairly strong against Florida this weekend, especially given their penchant for switching up their DPS looks between Lane "Surefour" Roberts, Brady "Agilities" Girardi, and Andreas "Logix" Berghmans. There's also the potential to see more Doomfist combinations, including the Doomfist-Sombra duo (Hackfist) that worked well for the Houston Outlaws this past weekend in Houston. If teams want to stick to pairing Mei with a sniper, we could see a rise in Hanzo priority this weekend as well.

Teams that would do well on this hero pool but we won't see due to unfortunate circumstances

Pour one out for the Chengdu Hunters and Shanghai Dragons, both of which would likely perform very well with more dive-based compositions, and potential rises in Pharah and Wrecking Ball play.