Arizona Diamondbacks: 5 unanswered questions before the wild card game

Who should start at catcher?
As of yesterday, manager Torey Lovullo still had not decided whether Jeff Mathis or Chris Iannetta would start behind the plate.
Both veteran backstops have caught Greinke well this season. Both know what the right hander likes to throw in certain situations and either catcher will have a great game plan.
Mathis threw out more attempted base stealers than Iannetta (34.5 to 19.4) and his catcher’s ERA of 3.51 is superior to Iannetta’s.
But Mathis saw his first game action since Aug. 21 in the Kansas City series and as a result, Iannetta caught 158 more innings than Mathis.
Iannetta is also the better hitter and has a knack for hitting a clutch home run or double with runners in scoring position.
Mathis’ relationship with Greinke cannot be overlooked, but Greinke did not miss a beat with Iannetta behind the plate and the D-backs need “CI’s” bat in the lineup.