Seattle Mariners: A closer look at the 4 new pitching prospects

After the Seattle Mariners’ recent flurry of activity in the trade market, we review their new pitching prospects.

The Seattle Mariners have made their intentions crystal clear, after trading the likes of James Paxton, Edwin Diaz and Robinson Cano. This team is going all-in on the rebuild.

M’s fans will have to be patient, as it’s all about bringing in and developing prospects now. In this respect, the recent flurry of trade activity has improved the farm system from its standing as one of the worst in the Majors, to around mid-range.

The addition of four pitching prospects appear particularly intriguing. As such, let’s take a closer look at each of the new arms and break down what they bring to Seattle.

1) Justus Sheffield

• Age: 22
• Throws: Left
• Drafted: Round 1 (31st) in 2014
• Obtained from: New York Yankees

When you’re the Yankees’ number one prospect, it has to count for something. Apart from this, Sheffield is widely considered the best of all the prospects the Mariners have acquired during this offseason. (In fact, he’s now the team’s top-rated prospect.)

The 22-year-old spent the majority of this past season in Tripe-A with the Scranton/Wilkes-Barre RailRiders. He went 6-4 in 20 games — including 15 starts — while recording a 2.56 ERA, 1.16 WHIP and 8.59 strikeouts per nine innings. (He also made his Major League debut with the Yankees in September, pitching 2.2 innings in three brief appearances.)

Sheffield has all the talent, athleticism and potential you’d expect in a top-rated prospect. His two main pitches are his slider and a fastball which regularly reaches 94 mph.

However, the Tullahoma, Tennessee native isn’t without his flaws. His biggest one is a lack of consistency and control with his command.

In this respect, it’s up to the Mariners to take care of the command issue, while honing Sheffield’s overall skills. The outcome of how he is handled, will mean the difference between him becoming a starter or a reliever in the Majors.

Prediction: Middle of the rotation

2) Justin Dunn

• Age: 23
• Throws: Right
• Drafted: Round 1 (19th) in 2016
• Obtained from: New York Mets

The acquisition of Dunn is one the Mariners are particularly excited about. They regularly scouted him back in 2016 and at one point seemed all but set to draft him, before looking elsewhere.

The 23-year-old isn’t as highly rated as Sheffield, but he is still an extremely intriguing prospect. He was widely considered the Mets’ third best prospect heading into the 2018 season, and he now holds the same position with the Mariners.

Like Sheffield, Dunn has a rocket for an arm, capable of reaching the high-90s with his fastball. As per various scouting reports, his breaking pitches could be a dangerous weapon if applied correctly.

The Free Port, New York native split his time between High-A (nine starts) and Double-A (15 starts) during 2018. He stats at Triple-A alluded to his inconsistency, with an ERA of 4.22 and 1.36 WHIP, compared to 10.54 strikeouts per nine innings and essentially averaging six innings per outing.

Dunn’s talent, which includes four pitches, gives him every chance of becoming a starter. However, fans should be weary of the genuine possibility he will not entirely fulfill his potential.

Prediction: Bullpen

3) Erik Swanson

• Age: 25
• Throws: Right
• Drafted: Round 8 (246th) in 2014
• Obtained from: New York Yankees

Coming in as part of the return package for Paxton, Swanson may not be perceived as a particularly appealing addition. However, he represents more than just an add on to get the trade completed.

The 25-year-old has been immediately ranked as the Mariners’ 11th best prospect. And in general manager Jerry Dipoto, he has a real fan.

Dipoto believes Swanson is ready for the big leagues and he will be given a shot at making the starting rotation out of spring training. Regardless, expect him to make his debut in the Majors in 2019.

The Terrace Park, Ohio native spent time pitching at three different levels during 2018, recording a 2.66 ERA and 139/29 K/BB ratio over 121.2 innings. In Triple-A specifically, he posted a 3.86 ERA and 1.06 WHIP, with a 78/14 K/BB ratio.

Swanson has excellent command and a fastball which regularly reaches the mid-90s. However, his lack of a strong second pitch will be key in determining the level of his success with the M’s.

Prediction: Back-end of the rotation

4) Gerson Bautista

• Age: 23
• Throws: Right
• Drafted: Signed at international free agent in April 2013
• Obtained from: New York Mets

When someone tells you they’ve found a pitcher who averages 98 mph on their fastball, you’re going to sit up and take notice. And in Bautista, that’s who the Mariners have acquired.

However, any excitement has to be immediately tempered; why else would the Mets be willing to trade the 23-year-old? The reality is he has trouble controlling it, as highlighted by giving up an average of 4.1 walks per nine innings in Triple-A during 2018.

Bautista does have a 85 mph slider which offers some potential as a secondary pitch. However, it is lacking consistency at this stage for the Mariner’s 28th ranked prospect.

The San Juan, Dominican Republic native made the first five Major League appearances of his career this past season. There was little to write home about however, as he registered a 12.46 ERA, 3.00 WHIP and 3/5 KK/BB ratio over 4.1 innings.

Understandably, it’s too soon to know for sure where Bautista’s career is headed. He could theoretically be a closer with his rocket arm, but there’s a strong possibility the M’s have other plans for him.

Prediction: Middle reliever