Ronald Bolanos

The Mariners have acquired first baseman/designated hitter Carlos Santana and cash from the Royals in exchange for right-handers Wyatt Mills and William Fleming, per a team announcement. The trade paves the road for the Royals to take an overdue look at top prospect Vinnie Pasquantino, whose contract has been formally selected from Triple-A Omaha, according to the team. Right-hander Ronald Bolanos has been designated for assignment in order to open a spot on Kansas City’s 40-man roster.

Monday’s trade closes the book on a generally underwhelming Kansas City tenure for Santana, who inked a two-year, $17.5MM contract in advance of the 2021 season but has yet to round into the form that made him such a valuable contributor for years in Cleveland. The switch-hitting 36-year-old tallied 871 plate appearances with the Royals and posted just a .215/.326/.341 batting line — about 12% worse than league-average after weighting for park and league, by measure of wRC+.

Santana managed to turn things around in recent weeks, however, and has shown enough this month for the Mariners to take a low-cost look now that they suddenly find themselves in need of a first baseman. Ty France, Seattle’s most consistent hitter this season, recently landed on the injured list and figures to be out for a good bit longer than that 10-day minimum, given the diagnosis of a Grade 2 flexor strain. Santana shouldn’t be expected to fully replace France’s brilliant .316/.390/.476 batting line, but he’s managed a .298/.405/.468 output himself over his past 27 games and 111 plate appearances.

In all likelihood, the Royals are paying the vast majority of what remains on Santana’s contract. He’s still owed the balance of this year’s $10.5MM salary (about $5.8MM), and that number will increase based on plate appearances. Santana, who already has 212 plate appearances this season, will earn an additional $75K for every 25th plate appearance from 300 to 525.

It’s not the first time the Mariners have acquired Santana, though whenever he takes the field in a Mariners jersey, it’ll be his first actual game with the team. Seattle actually acquired Santana alongside J.P. Crawford in the deal that sent Jean Segura, Juan Nicasio and James Pazos to the Phillies back in Dec. 2018. However, not two weeks later, Santana was traded to Cleveland in the three-team swap that brought Edwin Encarnacion to Seattle. Encarnacion spent a half season slugging as the Mariners’ designated hitter before being flipped to the Yankees for righty Juan Then.

This time around, it’ll be a pair of right-handers going to Kansas City in exchange for the final three-plus months of control over Santana. Of the two righties in question, only Mills has big league experience thus far. The 27-year-old has pitched a total of 21 1/3 frames over the past two seasons but struggled to a 7.59 ERA with worse-than-average strikeout and walk rates in that time (17.3% and 10.2%, respectively).

Mills, the No. 93 overall pick in 2017, has more interesting but also inconsistent numbers in the upper minors. The sidearming righty fanned a whopping 44.7% of his opponents through 28 2/3 innings of Triple-A ball last year, for instance, but that rate has been halved so far in 2022 over the course of 19 2/3 innings. There’s no velocity change between his ’21 and ’22 campaigns, though Mills did throw more fastballs at the expense of some slider usage during this year’s small sample of 8 2/3 big league innings. The 6’4″ righty has never ranked as one of the Mariners’ very best prospects, but Baseball America has listed him among Seattle’s top 25 farmhands dating back to the time he was drafted.

Fleming, meanwhile, is a 23-year-old righty whom the Mariners selected in the 11th round just one year ago. He generally hasn’t been considered among the Mariners’ best prospects either — though FanGraphs’ Eric Longenhagen did tab him 28th earlier this year — and has posted fairly pedestrian numbers in Class-A Modesto despite being a former college arm who’s older than his average opponent at that level. So far, Fleming has tossed 67 2/3 innings over 14 starts and logged a 4.92 ERA with a 20.7% strikeout rate against an 8.4% walk rate.

For the Royals, the arms received in exchange for Santana are secondary when it comes to this trade. The greater purpose of the swap was to at last open playing time for the 6’4″, 245-pound Pasquantino, who has mashed his way into top prospect status by dominating at every minor league stop, including Triple-A this season. So far, Pasquantino has taken 296 turns at the plate for the Storm Chasers and posted a huge .280/.372/.576 batting line with 18 home runs, 16 doubles two triples and more walks (37) than strikeouts (36).

Given his size and lack of speed, Pasquantino is locked into a first base-only (or designated hitter) profile, but there’s every indication so far that his bat will play in the Majors. Scouting reports at Baseball America and FanGraphs indicate that he’s improved enough with the glove to be average or slightly better, and Pasquantino has never posted an OBP lower than .371 or a slugging percentage lower than .560 at any minor league level. And, given the dearth of strikeouts in his game, he’s been able to maintain a .293 average throughout his minor league tenure to date.

Even without much defensive value to prop up his value, Pasquantino ranks as the game’s No. 57 prospect over at Baseball America. He checks in 95th at FanGraphs and 98th at MLB.com, with all three scouting reports praising his plus (or better) hit tool and above-average power.

The organizational hope is that between Pasquantino and fellow slugger Nick Pratto — also a first base-only, top-100 prospect — they’ll have their first base and DH slots covered for years to come. Pasquantino’s promotion to the Majors is late enough that he should avoid Super Two status, and he’ll be controllable for at least six full seasons beyond the current campaign.

As for the 25-year-old Bolanos, he’s seen action with Kansas City in each of the past three seasons but has posted pedestrian numbers on the whole. Once a notable Padres signing out of Cuba, he was traded to the Royals alongside Franchy Cordero in the 2020 trade that sent Tim Hill to San Diego. He’s since combined for 28 1/3 innings of 4.76 ERA ball with a lackluster 24-to-17 K/BB ratio.

Bolanos does have a respectable 4.42 ERA in 18 1/3 innings this year, but his average fastball of 93.6 mph is down about two miles per hour from its peak and that ERA comes in spite of an even number of walks to strikeouts. Add in that he’s limped to a 5.49 ERA in 19 2/3 Triple-A frames this season, and it was enough for the Royals to decide they’re willing to move on. Of course, the DFA doesn’t necessarily spell the end of his time in the organization. Kansas City will have a week to trade Bolanos if there’s interest, but the Royals can also attempt to pass him through outright waivers at some point in the next week. If he goes unclaimed, he’d remain with the organization but no longer occupy a spot on the 40-man roster.