These 5 prospects could impact NL West race

The National League West race has already been plenty surprising, but it also feels ... incomplete. The Dodgers and Giants are both without their aces. The D-backs are down their best everyday player. The standings seem a bit topsy-turvy right now, but it's also easy to remind yourself that these teams are sure to change over the coming months.
And that's not just a matter of injuries. Every team in the division has at least one prospect knocking on the door, players who could shape the race in their own ways if given the opportunity.
Here's a look at one prospect to watch for each club.

D-backs
Prospect: Jon Duplantier, RHP
MLB Pipeline rankings: D-backs' No. 1 prospect, overall No. 68
Why you should keep an eye on him: A year after starring in the notoriously hitter-friendly California League, Duplantier has handled the jump to Double-A with ease. And he's done it while keeping his strikeout rate high and slashing his walk rate. The problem, of course, is that Arizona has plenty of pitching, even with Taijuan Walker out. What the Snakes need is a bat. Still, Duplantier has risen rapidly -- he's at his fourth level after just 30 professional starts -- so he could be putting himself in position to help if there's a need down the road sometime.
ETA: It will most likely be 2019, but Duplantier is doing everything he can to force the issue.

Dodgers
Prospect:Alex Verdugo, OF
MLB Pipeline rankings: Dodgers' No. 2 prospect, overall No. 30
Why you should keep an eye on him: We could have gone with Walker Buehler here, but it seems likely he'll be losing his prospect status sooner than later. He's up, and it seems he's up to stay. Verdugo appears to have a tougher fight for a spot on the big league roster. He has the ability, though. Verdugo has excellent bat-to-ball skills, and he's using them to hit .300 yet again. He also has an exceptional arm and is at least a big league-caliber right fielder, if not a potential center fielder. It's a bit of an unusual package -- Verdugo is not really a leadoff man since he doesn't walk much, and he's not really a middle-of-the-order hitter since he doesn't hit for power. But he hits, he catches, he throws and he held his own in an audition earlier this year. Verdugo will help the Dodgers again before the year is out.
ETA: September at the latest, but it will be surprising if it's not sooner.
Giants
Prospect:Austin Slater, OF
MLB Pipeline rankings: Giants' No. 5 prospect
Why you should keep an eye on him: In short, because Slater is raking. And one of baseball's oldest truths is, if you hit, they'll find a spot for you. In classic Giants fashion, Slater is not a highly touted tool box. He's just a guy who's producing. Slater has refined his strike zone over the years and he's torching the PCL to the tune of .396/.472/.679. He is 25 and in his fifth year of pro ball, so he may not have a ton of growth remaining in his game. But Slater is hitting, and that's the surest ticket to The Show.
ETA: It's kind of now or never; if Slater can't force his way into the mix before the year is out, it's hard to see when he will.

Padres
Prospect: Luis Urias, IF
MLB Pipeline rankings: Padres' No. 3 prospect, overall No. 32
Why you should keep an eye on him: Urias doesn't have quite the hype, or the famous name, of fellow future Friar Fernando Tatis Jr. But he is closer to the Majors than Tatis, and at least arguably having a better year. Urias is the more polished of the two prized infield prospects, with an advanced approach that has produced a .407 OBP at Triple-A. He looks like he'll play a solid second base in the big leagues. Urias may never be a basher, but he's shown some improved pop this year, which will help him keep drawing walks at the top level.
ETA: It could very well come after the non-waiver Trade Deadline, once San Diego clears some space for him.

Rockies
Prospect:Ryan McMahon, 1B
MLB Pipeline rankings: Rockies' No. 2 prospect, overall No. 38
Why you should keep an eye on him: You may not have heard, but the Rockies haven't gotten an awful lot of production out of first base this year. And McMahon can hit, posting a .355 average in the Minors last year. He's scuffled some this year, including in a 60 plate-appearance look with the big club, but he's come on since he was sent back down to Triple-A. Meanwhile Ian Desmond is hitting .180 with a .233 OBP, and has a .671 OPS since joining the Rockies last year. There's also been talk of giving McMahon a look at second base, but that seems like a tough ask. Still, it's an indication that he's on the big club's radar.
ETA: Like Verdugo, McMahon is certain to get a September callup, and likely to get another before then.