FanGraphs Weekly Power Rankings: July 1st–7th

These next few weeks should go a long way towards separating the wheat from the chaff in the postseason race. For the teams on the fringe of the playoff picture, a timely hot streak could convince them to upgrade at the trade deadline, while a cold snap could push them into seller mode. With the All-Star break looming, it’s time for some serious introspection as teams gear up for the stretch run.

This season, we’ve revamped our power rankings. The old model wasn’t very reactive to the ups and downs of any given team’s performance throughout the season, and by September, it was giving far too much weight to a team’s full body of work without taking into account how the club had changed, improved, or declined since March. That’s why we’ve decided to build our power rankings model using a modified Elo rating system. If you’re familiar with chess rankings or FiveThirtyEight’s defunct sports section, you’ll know that Elo is an elegant solution that measures teams’ relative strength and is very reactive to recent performance.

To avoid overweighting recent results during the season, we weigh each team’s raw Elo rank using our coinflip playoff odds (specifically, we regress the playoff odds by 50% and weigh those against the raw Elo ranking, increasing in weight as the season progresses to a maximum of 25%). As the best and worst teams sort themselves out throughout the season, they’ll filter to the top and bottom of the rankings, while the exercise will remain reactive to hot streaks or cold snaps.

First up are the full rankings, presented in a sortable table. Below that, I’ve grouped the teams into tiers with comments on a handful of clubs. You’ll notice that the official ordinal rankings don’t always match the tiers — I’ve taken some editorial liberties when grouping teams together — but generally, the ordering is consistent. One thing to note: The playoff odds listed in the tables below are our standard Depth Charts odds, not the coin flip odds that are used in the ranking formula.

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The Orioles solidified their grip on the AL East lead by winning series against the Mariners and A’s last week. And while a 19-8 loss on Saturday won’t do their actual run differential any favors, their BaseRuns run differential is the best in the American League by a pretty wide margin. They’ll have an opportunity to put some serious distance between themselves and the Yankees in a huge three-game series this weekend.

The Guardians bounced back after their series loss to the Royals a couple of weekends ago with a pair of series wins against the White Sox and Giants last week. They’re outperforming their BaseRuns record by the widest margin in baseball — a whopping nine wins — and their absolutely elite bullpen and fantastic clutch hitting are the big reasons why. One of those things seems more sustainable than the other, and both the Twins and Royals have done well to mostly keep pace in the AL Central. It’ll be interesting to see what kinds of upgrades Cleveland pursues at the trade deadline to help ward off those two challengers.

The Phillies have gone a respectable 5-4 since putting both Bryce Harper and Kyle Schwarber on the IL a week and a half ago, though they did lose their series against the Braves over the weekend. Much of that success is thanks to the other star in Philadelphia’s lineup, Trea Turner; he collected nine hits and four home runs last week. Thankfully, Schwarber should be coming off the IL this week, with Harper likely be right behind him.

After a brief hiccup against the Giants and Diamondbacks, the Dodgers got back to winning this past weekend, taking two of three from the Brewers at home. They’ll face a tough challenge with a three-game set in Philadelphia this week.

The red-hot Astros ran into the almost equally hot Twins this past weekend and their three-game set was filled with drama. Seven batters were hit by pitches in the series, forcing Jose Altuve, Yordan Alvarez, and Carlos Correa to miss at least a game. Though none of the injuries seemed serious, there was certainly no love lost between these two teams…

Facing a challenge from the Cardinals in their division, the Brewers didn’t wait around to make an upgrade to their patchwork rotation, trading for Aaron Civale last week. He should provide some league-average innings for Milwaukee. The Brewers could still use another starter or two to feel really good about their chances of hanging on to the division lead — Dallas Keuchel just isn’t the solution for a playoff-bound team — but it’s unclear how much more prospect capital they’re willing to part with.

The Red Sox continued their ascent up the standings with five wins last week, including two in New York in a huge series win over the struggling Yankees…