Born: January 9, 1998
Height: 6’6″
Weight: 225
Bats: Right
Throws: Right
Drafted: 6th Round, 184th Overall, 2019
How Acquired: Draft
College: Stanford University

Matthiessen was a two-way player at Stanford.  The Pirates announced him as a right fielder and that seemed to be the preference of most scouts, due to potential for increased power if he improves his approach at the plate.  He’s become strictly a first baseman in the Pirates’ system.  As a junior, he was Stanford’s second best hitter, posting a 322/399/553 line, with a dozen home runs.  Strikeouts, though, are a problem; he fanned in a quarter of his ABs.  Matthiessen didn’t play regularly in his sophomore year but had seven home runs and slugged .598.  He didn’t bat at all as a freshman.  As a pitcher in his junior year, he fanned 55 in 53.1 IP in a swing role, with an ERA of 3.71.  He signed for $2500 under the slot value.

A-:  220/303/340, 159 AB, 5 2B, 1 3B, 4 HR, 18 BB, 46 K, 2-2 SB

Matthiessen played for West Virginia, where he split his time between first base and right field.  Like nearly all of the Pirates’ college position player draftees in recent years, he struggled at the plate in the New York-Penn League.  He did show a little power, but struck out in over a quarter of his plate appearances.  His numbers were close to the league averages of 232/313/337, but you’d like something better than that from a corner player.


A:  256/431/538, 39 AB, 3 2B, 1 3B, 2 HR, 12 BB, 21 K
A+:  245/319/437, 277 AB, 14 2B, 13 HR, 30 BB, 107 K, 1-4 SB

Matthiessen had one of the stranger seasons you’re likely to see.  He started off as the first baseman at Bradenton.  In his first 17 ABs, he struck out 12 times.  In his last game for the Marauders, though, he hit two doubles and a home run, and drove in six; that one game accounts for his good batting line at the level.  He was promoted to Greensboro when Nick Gonzales got hurt.  He started there 1-for-21 with 13 strikeouts.  He put up a .541 OPS in June, but in July he started hitting.  He had a .941 OPS in August and .809 in September.  In 23 August games, Matthiessen hit eight home runs and drove in 32.  So his whole season was a succession of spells where he either struck out constantly or hit for a lot of power.  To add to the quirkiness, in a wild, 12-inning game in August, he entered as a pitcher in the 12th.  He got bombed for six runs, but Greensboro scored seven in the bottom half to win, 15-14, with the final blow being a walk-off grand slam by Matthiessen.  So he also got the win.  Defensively, he mostly played first, but he got into 11 games in right for Greensboro.

AA:  171/191/342, 41 AB, 1 2B, 2 HR, 1 BB, 14 K

Matthiessen opened at Altoona, but his season didn’t last long.  After he’d played 11 games, he suffered a shoulder injury and missed the rest of the year.

Matthiessen has so much power that it’s tempting to imagine what he’d could do if he just made a little more contact.  He’ll probably return to Altoona in 2023.

2023: Minor league contract
Signing Bonus: $261,200
MiLB Debut: 2019
MLB Debut:
MiLB FA Eligible: 2025
MLB FA Eligible:
Rule 5 Eligible: 2022
Added to 40-Man:
Options Remaining: 3
MLB Service Time: 0.000
June 4, 2019: Drafted by the Pittsburgh Pirates in the 6th round, 184th overall pick; signed on June 17.