With the Arizona Diamondbacks’ magic number sitting at four games, the team could clinch a spot in the postseason for the first time since 2011.

FanGraphs currently has the D-backs’ playoff odds at 100 percent, and they hold a 5.5 game lead over the Colorado Rockies for the right to host the N.L. Wild Card Game on Oct. 4.

So what is the Diamondbacks’ biggest lineup question entering October? ESPN senior writer David Schoenfield has come up with an answer that may surprise you — Chris Iannetta’s spot in the batting order.

Is Chris Iannetta the unlikeliest No. 2 hitter for a playoff team? Yes.

One thing to note: The odd thing about manager Torey Lovullo’s lineups is that he has Paul Goldschmidt and J.D. Martinez in the fourth and fifth spots, no matter the pitcher. Jake Lamb and A.J. Pollock rotate hitting third.

Schoenfield certainly presents an interesting take. In 69 at-bats in the two-hole, the 34-year old is hitting .333 with a .432 on-base percentage, a .954 OPS, seven doubles, 10 RBI and 10 runs scored.

Here is how his numbers batting second compare to other spots in the lineup:

Batting 2nd: .333 average, 69 at-bats, .432 on-base percentage
Batting 4th: .375 average, 8 at-bats, .444 on-base percentage
Batting 5th: .125 average, 8 at-bats, .125 on-base percentage
Batting 6th: .100 average, 30 at-bats, .250 on-base percentage
Batting 7th: .239 average, 88 at-bats, .306 on-base percentage
Batting 8th: .225 average, 40 at-bats, .367 on-base percentage
Batting 9th: .300 average, 10 at-bats, .417 on-base percentage

Before he got injured, infielder Chris Owings had success batting second (.352 average in 71 at-bats). Nick Ahmed also had success, (.342 average, 38 at-bats), albeit with a much smaller sample size. Daniel Descalso is 3-for-5 in the two-hole this season.

Owings is eligible to return to the D-backs for their last series of the season in Kansas City. If that happens, it will be interesting to see where Iannetta slots in.

In addition to his success in the two-hole, Iannetta has been swinging a hot bat. The D-backs’ backstop has hit safely in 13 of his last 17 starts (.339 average, 21-for-62) and has reached base safely in 20 of his last 25 games (.308, 24-for-78 with 16 walks).

Remarkably, 29 of Iannetta’s last 51 hits have gone for extra bases (17 doubles and 12 home runs), and 50.1 percent of his hits this season have been extra base knocks.

The offense broke out in San Diego on Wednesday, but several big bats are in a slump. Paul Goldschmidt is hitting .182 this month and Jake Lamb is hitting .183.

In reference to Schoenfield’s comments about Lovullo’s lineups, recent games have seen Goldschmidt bat third and Martinez hit fourth.

Maybe Schoenfield chose Iannetta as the D-backs’ biggest lineup question because it is rare for a catcher to hit second.

But, is he really the offense’s biggest question mark right now?