The Brewers have had an incredible season fueled by a talented team and honestly, some unfortunate injuries to all three of their division rivals. With less than 40 games left in the season, the Brewers have put themselves in a very good position, not just to make the playoffs but win the NL Central division. However, the Reds and the Pirates are about to get stronger with the return of some important players. A this point though, it might be too little too late.
The Reds are playing for a Wild Card spot at this point. After losing both games in a double header yesterday to the Rockies, the Reds have found themselves 8.5 games back of the Brewers. They're also 4.5 games back of the second wild card spot with 3 teams ahead of them. They're not out of the playoff picture yet, but things are getting pretty dire in Cincinnati.
They're probably quite happy to activate Brandon Phillips. They'd probably be a lot happier to activate Joey Votto, but that's not happening. In Phillips' absence the Reds have gone with a combination of Kristopher Negron (118 wRC+, 3.7 Def in the second half), Ramon Santiago (73 wRC+, 0.9 Def), and Skip Schumaker (76 wRC+, -2.6 Def). Before his injury Phillips was hitting for a 93 wRC+ and fielding quite well earning a 6.7 in Fangraphs' defensive metric. So while Phillips is clearly the superior defensive player, and an offensive upgrade from Santiago and Schumaker, Negron was hitting better. I think overall it's an upgrade, but not a terribly meaningful one.
The Reds play the Brewers 6 more times, the Pirates 6 more times, and the Cardinals 10 more times (including a 3 game series this week). If the Reds are going to have an impact on the Brewers season from here on out, it's very likely going to be in how many games they can take from the Pirates and the Cardinals (or conversely how many they give up to them). I happen to believe they're the worst of the three rivals but they do have the best run differential (Reds at +19, Pirates at +9, Cards at -8!). So there is hope in that.
I believe the Pirates represent the bigger threat. The Reds have the best pitching staff but, after the Brewers, the Pirates have the strongest offense. Their pitching staff isn't exactly a disaster either. Both of those aspects of their team are looking to get better this week. Gerrit Cole is supposed to be activated from the disabled list and pitch on Wednesday. Andrew McCutchen may also make his return this week.
Gerrit Cole was pitching reasonably well before going on the DL (3.78 ERA/ 3.75 FIP/ 3.56 xFIP). However, Charlie Morton has also pitched well (3.84 ERA/ 3.78 FIP/ 3.83 xFIP) and he just went on the DL. So for right now, the rotation is arguably just treading water. When Morton returns it will get another boost, but that won't be until some time in September and again, could be too late to matter significantly.
Andrew McCutchen's possible return is more meaningful. Before his injury he was hitting 311/411/536, 167 wRC+. That's a huge bat to get back, but it also pushes Travis Snider back to a back-up role. Snider hasn't been bad (119 wRC+), but an outfield of Marte, McCutchen, and Gregory Polanco is probably Pittsburgh at their best.
The Pirates have 6 games left against the Brewers, Cardinals, and Reds. They're 5.5 games back of the Brewers and 1.5 games back of the second Wild Card team (tied with the Braves). Obviously the Pirates are in a much better spot than the Reds, but overcoming a 5.5 game deficit with 6 weeks left is a tall order.. They play the Brewers this weekend, but Gerrit Cole won't be pitching in the series. If McCutchen does return it remains to be seen how much his injury, which can't be fully healed, is still affecting him.
So even though they might be technically in a better position for the rest of the season, they might still be the team that lost 7 of the last 10 games when they come to Milwaukee this weekend. If that's the case then maybe the Pirates will play a similar role to the Reds in that they'll help the Brewers (by beating the other division rivals), more than they hurt the Brewers (unless they drop a bunch of games to the Cardinals).
If the Brewers can keep their hot streak going through the weekend they could really bury the Pirates and that's good because they're arguably the best team in the division next to the Brewers. The Reds basically already out of the race for the division and are only getting marginally better with the return of Phillips. They're getting a better defense and that could help the pitching staff, but it's their offense that needs the help and Phillips isn't that guy. What was once looking like the NL Central Shredder of a September schedule is looking a lot more friendly to the Brewers.
Statistics courtesy of Fangraphs