No MLB team wants to lose their starting catcher to injury. While many backstops don't provide a ton of offense -- the league-average hitting numbers at the position this season include a .245/.314/.407 triple slash and 88 wRC+ -- they play a huge part in the success or failure of a pitching staff. And when they do provide above-average offense, it's an even bigger loss.

That's probably how the Chicago Cubs felt when their incumbent starter and budding star, Willson Contreras, hit the disabled list with a hamstring injury. After all, he was having a great year and was in the midst of a ridiculous second-half power surge. However, instead of having to rush him back because the National League Central is very much still up for grabs, they don't have to because of how Alex Avila, an acquisition they made prior to the non-waiver trade deadline, has played in his absence.

A Budding Superstar

For a 25-year-old backstop with just 178 MLB games under his belt, Contreras hasn't wasted any time in showing how important he is to Chicago. During this period of time, he's slashed .277/.348/.506 with 33 home runs, a 123 wRC+ and a 5.0 fWAR.

A crowded depth chart at the position in 2016 meant he had to be versatile, which he accomplished by splitting time between left field (24 games, 180.2 innings) and catcher (57 games, 389.2 innings), but that hasn't been the case this year -- he's spent 94 of his 102 games played behind the plate and has thrived in that role.

He's proved his worth with the glove, and is continuing to do so in the batter's box, too. Among catchers with at least 300 plate appearances this year, his 121 wRC+ is fifth-best, while his 2.8 fWAR is fourth-best. His hamstring injury will keep him sidelined until mid-September (which would be the best-case scenario), and while that's not ideal, Avila softens the blow quite a bit thanks to a career year.

An Elite Replacement

Although having Avila behind the plate is a step back defensively compared to Contreras (-2 Defensive Runs Saved over the last three seasons), he makes up for it with his offensive production. As we can see in the table below, Avila's OPS and wRC+ are better than his fellow backstop, and he's not too far behind him in fWAR.

These two are very different hitters, and they've taken different paths toward being two of the more successful hitters at the position in 2017.

Avila's 30.3% strikeout rate and .208 ISO aren't quite as solid as Contreras' numbers in the same categories (.245 ISO and 24.1% strikeout rate), but it's not a huge difference in power. Plus, Avila's .393 on-base percentage is far superior to Contreras' .342 mark because he walks more often (16.2% to 8.7%), which is awfully helpful in what's been a more potent Cubs lineup in recent weeks.

Looking Toward the Stretch Run

The biggest red flag at the moment for Avila is his BABIP, which is on track to be a single-season career high at .375. A number that high is always something to be wary of, but he has a chance to keep it up if his hard-hit rate stays around the 49.1% it's at right now (that's quite an increase compared to the 32.6% mark he posted in 2016). Even if he falters a bit from these present numbers, watching his production completely crater probably won't happen in the span of a few weeks. And, for the Cubs, that's all they need until Contreras is ready to return.

Chicago acquired Avila because they needed some more depth after designating Miguel Montero for assignment earlier in the year. They weren't anticipating to plug him in this often down the stretch, but he's been producing like another elite offensive catcher, and most teams don't even have one. Only 14 catchers have a wRC+ above 90 this year, and just 10 are currently above 100. There aren't many options to choose from with regard to finding offense at the position, but the Cubs have two of the best ones out there.

At a crucial time in the year when the importance of every game is magnified, Contreras' injury came at the worst possible time. However, the presence of Avila has made the loss much more bearable, and even allowing the club to be patient with their young backstop as his injury heals.