Gage Jump is pitching like a man who belongs in the majors. The A's aren't sure they agree yet, and for now, they don't have to. 

Jump is either the A's second-or-third-best prospect depending on which minor-league rankings you're looking at, but everyone agrees he's firmly within the top-100 prospects in baseball. Some even have him as a top-50 guy. 

The talent is there, and after a slow beginning to the season, Jump has taken the step forward that could see him in Sacramento before long. I wrote earlier this month that with a strong month of May, the lefty could be in the big leagues by June. The A's two series in Las Vegas next month were the ones that made sense both in terms of timeline and spectacle ahead of the A's move. 

In his start on Wednesday night, he pitched past 4 2/3 innings for the first time this season, giving up four hits across seven scoreless innings, allowing zero walks and striking out nine. Over his last two starts Jump has totaled 11 scoreless innings, surrendering eight hits, one walk and racking up 15 strikeouts. 

That's exactly the kind of production that he needs to show in order to push his way to the A's roster in Sacramento. 

While Jump is on the right path, the track record just isn't long enough in Triple-A. Last night's start is his only one that has been as many as five innings this season, and to be in the A's rotation, he's going to have to offer innings. Bringing up a left-hander with talent isn't exactly a need right now. Effective innings are. 

While Jacob Lopez has struggled to a 6.14 ERA, he has been able to provide five innings in six of his nine starts. The A's offense has typically shown up in support, too, as he holds a 3-2 record, tied with Jeffrey Springs for the second-most wins on the club. 

Lopez would appear to be Jump's biggest obstacle in the starting rotation, barring injury. The hurdle he'll have to clear is going deeper into games. 

That doesn't mean that Lopez should be tossed aside, however. Instead, he could be a huge piece of the bullpen, given that he's been an impactful arm the first time through a lineup. It's when he gets up to 65+ pitches and into the fifth and sixth innings that he generally falters. 

The A's have been in need of a second left-hander in relief all season to pair with Hogan Harris, and while José Suarez is in the role currently, his results haven't been terrific, posting a 7.08 ERA on the season, and a 13.50 ERA in his two innings since joining the A's from Seattle. 

Jump's last two outings continue to make his case for a call-up a more legitimate one. The problem is that the A's don't have much incentive to push him to the majors immediately. 

The more likely outcome is that Jump will continue to stack innings with Las Vegas, making his case and forcing the A's hand. If Lopez continues to struggle while Jump surges to close out May, an opportunity may arise to shake up the rotation. 

There is just no need to force it. He's expected to be a potential ace of the rotation, and the A's will want to make sure he's ready before they make the call.