The Yankees lead the Majors in runs per game (5.99), which isn't terribly surprising. After all, they were second-best last year, they set the record for most home runs in a season (267), and all their 2018 work was done without DJ LeMahieu, largely without Luke Voit, and with Gary

The Yankees lead the Majors in runs per game (5.99), which isn't terribly surprising. After all, they were second-best last year, they set the record for most home runs in a season (267), and all their 2018 work was done without DJ LeMahieu, largely without Luke Voit, and with Gary Sánchez and Giancarlo Stanton having something less than their best seasons. They were expected to be one of the best offenses in the game in 2019, and they are.

It just hasn't been with the players you thought they'd be using. The second-string -- and in some cases, third-, fourth-, and fifth-string -- Yankees are the ones leading the charge, in a way we've rarely ever seen.

Here's the thing about the 2019 Yankees: No team has suffered more injuries. Their Opening Day infield -- and isn't this an all-time trivia question if they win the World Series -- of Greg Bird (1B), Gleyber Torres (2B), Troy Tulowitzki (SS) and Miguel Andújar (3B) played exactly one game together, and none of the non-Torres trio has been seen in pinstripes since May 12. Stanton has appeared in only nine games. Didi Gregorius missed the first two months.

You know who's been starring instead. Mike Tauchman, picked up from Colorado as outfield depth just before the season, enters Friday's game hitting .297/.373/.566 (after hitting his 11th homer in 62 games on Thursday) with excellent defense. Veteran outfielder Cameron Maybin -- who'd been on four teams in the previous two seasons, and was let go by outfield-needy teams in both San Francisco and Cleveland in 2019 -- was picked up in late April and is hitting .335/.411/.555. Gio Urshela, the out-of-nowhere savior at third base, is hitting .323/.367/.568 and just had his second multi-homer game in a row.

It doesn't stop there. Sánchez gets hurt? Backup Austin Romine is hitting .394/.432/.848 since entering on July 23 to replace him, and third-stringer Kyle Higashioka hit two homers on Wednesday night. Voit, Edwin Encarnación, and Bird all on the injured list? Fourth-string first baseman -- fifth if you count LeMahieu -- Mike Ford has gotten on base and scored a run in each of his four starts this week. Torres needs a break due to a core injury? The next man up would be Thairo Estrada, who posted a .280/.321/.520 line in 25 games earlier this season. They haven't even been able to find room for Clint Frazier, who has a .283/.330/.513 slash line in 209 plate appearances.

As Orioles manager Brandon Hyde told the Athletic's Lindsay Adler on Tuesday night, during a record-setting barrage of Yankees homers during their three-game sweep: “It’s not even their big boys either, which is pretty scary.”

He's right. And we can prove it.

"Have good players and don't have bad players" isn't exactly a revolutionary idea in baseball or any other sport, but baseball, in particular, isn't just about having stars. (If it was, Mike Trout would have more than one playoff appearance.) It's about having depth. This is why teams like the Dodgers of recent vintage can almost laugh off Clayton Kershaw's annual injured list trip, or Corey Seager missing nearly all of 2018. There's no "stars and scrubs." There's always someone else ready to contribute.

For the Yankees, there are so many good "someone elses" that they have given an incredibly low percentage of their plate appearances to what we'll term "under-performers," those with an OPS+ below 90. (OPS+ is a park-adjusted stat where 100 is "league average," but we're using 90 as a cutoff because having second- or third-string players being ever-so-slightly below average isn't a bad thing. Hitters with an OPS+ around 90 this year include Adam Jones, Josh Reddick and Joey Votto.)

Entering Thursday's action, the Yankees had given only 249 combined plate appearances to these under-performers -- just 5.6% their total (non-pitcher) plate appearances, easily the lowest of any team in 2019, where the Major League average is 33%. As you might expect, there's a great deal of correlation between "giving fewer plate appearances to unproductive players" and "scoring more runs." While these numbers will change slightly on a daily basis as players fall below or get above 90 OPS+, you get the point -- the Yankees simply don't have hitters coming up who haven't added value.

It's actually one of the lowest of any team in history, at least dating back to 1921. We're looking at over 2,500 team seasons over the last century here, and only a dozen -- or about half of 1% -- have had a lower percentage of plate appearances going to unproductive players.

Again: don't give playing time to poor players and you'll do well is not next-level thinking, but of those 12 teams, five won the World Series -- the Big Red Machine and a handful of Berra/DiMaggio Yankees teams among them -- and two others made it there. Among the remaining teams, all but one won at least 87 games; the 2005 73-89 Reds and their worst-in-the-NL 5.18 team ERA remind us that pitching matters.

If we up the minimum to average-or-better, so a 100 OPS+, the 2019 Yankees have the second-most players ever with at least 100 plate appearances of average-or-better performance. This is it. This is the entire point. Yes, LeMahieu has been stunningly good, and Judge and Sánchez have shown flashes of their best selves when healthy, but when forced to call upon reinforcements, the Yankees haven't been saddled with sub-replacement performance. They've barely missed a beat.

It's true that we haven't discussed the rotation, which hasn't been quite as successful trying to patch for the injured Luis Severino, and obviously looking just at offense doesn't tell you much about fielding. But if you've been watching this team survive -- thrive, really -- without a huge chunk of its expected lineup and wondering just how impressive it is that castoffs and Quad-A types have been able to keep the team afloat, the answer is what you expected. It's extremely impressive. It's how great teams end up having great seasons.

Mike Petriello is an analyst for MLB.com and the host of the Ballpark Dimensions podcast.