ESPN: Core question facing the Arizona Diamondbacks is about pitching

By all accounts, the first half of the Arizona Diamondbacks’ 2015 season has been a success.

After winning just 64 games all of last season, the D-backs have already notched 42 victories this year, putting them on pace for roughly 78 victories.

Whether they reach that mark, fall short or even surpass it remains to be seen, but according to ESPN’s Buster Olney, it will come down to pitching.

In an Insider piece going over 30 core questions — one for each team — Olney asks how much progress the team’s young starting pitchers will make in the weeks ahead.

Robbie Ray is getting better, clearly; will Rubby De La Rosa? How far will Patrick Corbin progress as he comes back from Tommy John surgery?

The answers to those questions will determine whether the D-backs will continue to be a factor in the 2015 playoff race and be a more dangerous threat in 2016.

Entering the All-Star break, Arizona’s starters have posted an ERA of 4.66, which places them 12th in the NL and 26th in all of baseball.

However, as Olney notes, there are some reasons to believe things will get better.

Ray has been a real bright spot for the team, posting a 3-4 record with a 2.16 ERA and 1.02 WHIP. And though Corbin struggled in his last outing prior to the break, it’s hard to see a world where Corbin — who won 14 games and had an ERA of 3.41 in 2013 — not showing gradual improvement as he works his way back into form.

As for De La Rosa, the 26-year-old leads the D-backs in innings pitched but has also been wildly inconsistent. There’s a reason why he is tied for the team lead with six wins, but also has an ugly 5.06 ERA.

Besides those three, Arizona’s rotation is made up of Jeremy Hellickson (6-5, 5.04 ERA) and Chase Anderson (4-3, 3.91 ERA). Archie Bradley, who began the season pitching very well but struggled following an injury, is still rehabbing in the minor leagues.