Projecting the Pittsburgh Pirates Opening Day rotation after their newest addition

The Pittsburgh Pirates’ pitching staff is the strongest part of the team, especially their rotation. If there’s any chance they’re good in 2025, their hurlers will do much of the heavy lifting, which will greatly assist an unimpressive offense.

The Pirates recently made a big addition to round out their pitching depth chart, signing veteran southpaw Andrew Heaney to a one-year contract. They nearly reunited with Jose Quintana, but they went with another experienced lefty to help out a young group.

With so much depth and talent, the Pirates are gearing up ti have one of the best units in the sport, but what will it look like in a month's time?

Projecting the Pirates Opening Day rotation after Andrew Heaney signing

Paul Skenes

Paul Skenes needs no explanation as to why he’s the Pirates’ No. 1 starter going into 2025. Skenes pitched 133 innings in his rookie year, working a 1.96 ERA (214 ERA+), 2.44 FIP, and 0.95 WHIP. The right-hander struck out about a third of opponents (33.1% K%, to be exact) with an outstanding 6.1% walk rate. Home runs nor hard contact were an issue either, as Skenes held opponents to a 0.68 HR/9 rate, 87.8 MPH exit velocity (76th percentile), and 5.7% barrel percentage (87th percentile). Skenes consistently hit triple-digits on the radar gun and had a 110 Stuff+ rating.

To say that Skenes’ rookie season was historic would be the understatement of the century. His ERA+ is the highest in 20+ starts in the Integration Era (since 1947). The next closest is the late Jose Fernandez’s 2013 rookie season, but he fell well short at 176. His WHIP is the best among rookies with at least 20 starts, and he also ranks top 10 in K/9 (11.5), hits/9 (6.4), and K:BB ratio (5.31). How can one not be excited to see what his encore looks like?

Jared Jones

Skenes isn’t the only hard-throwing young starter the Pirates have. Jared Jones, who flashed a ton of potential in 2024, is a budding star. Jones pitched 121 1/3 innings, working to a respectable 4.14 ERA, 4.00 FIP, and 1.19 WHIP. He struck out just over a quarter of opponents with a 26.1% K%. Despite struggling with walks in the minor leagues, Jones turned in an above-average 7.7% free pass percentage in his rookie year. Although, he did struggle to limit hard contact and homers, with a 1.33 HR/9, 89.6 MPH exit velo (27th percentile), and 9.8% barrel rate (13th percentile).

Jones still has a ton going for him heading into 2025. He had both a sub-4.00 SIERA (3.72) and xFIP (3.78). He averaged out at 97.3 MPH with his four-seam fastball and had a 102 Stuff+. Jones is reportedly tinkering with a two-seamer in spring training, which would definitely be a welcomed addition to his pitch mix and hopefully help him keep batters off balance even more than they were in 2024.

Bubba Chandler

The Pirates could easily open the 2025 season with three starters 23 years old or younger and who average out at 97+ MPH with their four-seam fastballs. Bubba Chandler, the Pirates’ top pitching prospect, did everything performance-wise to get serious consideration for an Opening Day rotation spot.

In 119 2/3 innings between Double-A and Triple-A, Chandler pitched to a 3.08 ERA, 3.10 FIP, and 1.02 WHIP. He struck out 30.9% of his opponents and put up a career-low 8.6% walk rate. The young right-hander allowed home runs at a 0.68-per-9 rate while holding opponents to an 85.3 MPH exit velo and 3.4% barrel percentage at Triple-A Indy.

Chandler is the Pirates’ most hyped non-Paul Skenes pitching prospect they’ve had since Gerrit Cole. MLB Pipeline ranks him as the 15th-best prospect, but Baseball America is exceptionally bullish, placing him at No. 7 on their top 100 prospects list. That also makes him eligible for prospect promotion incentive. The Pirates opened the year with Jared Jones in their rotation last season, so it’s not entirely unprecedented territory for this regime to do it again.

Mitch Keller

Mitch Keller would be a No. 2 starter on many teams. Instead, he could be a back end depth piece for Pittsburgh. Last season, Keller pitched to a 4.25 ERA, 4.08 FIP, and 1.30 WHIP in 178 frames. Although he posted a roughly league average 21.5% K% and 1.16 HR/9 rate, he cut his walk rate down to a career-low 6.5% mark. He was also around league average at limiting hard contact with an 88.8 MPH exit velocity (50th percentile) and 7.2% barrel rate (61st percentile).

Keller will look to avoid falling apart in the second half of the season. That has now happened two seasons in a row. He went into August of 2024 with a 3.30 ERA, 3.78 FIP, and 1.21 WHIP before struggling down the line. If he can avoid yet another late-season collapse (just like most of the Pirates’ roster had last season), he’ll likely be the fourth above-average pitcher in this rotation.

Andrew Heaney

The Pirates’ newest addition is likely going to slot in as their fifth starter, but that’s not a knock on Heaney. It’s more so a testament to how much pitching talent the Pirates have.

Heaney tossed 160 innings last season, working to a 4.28 ERA, 4.04 FIP, and 1.25 WHIP. The southpaw struck out 22.9% of opponents with a 1.29 HR/9 rate, but had a strong 5.9% walk rate. His BB% was top 20 in the league last season among pitchers who tossed at least 160 frames.

Heaney didn’t have a great exit velocity (89.6 MPH, 27th percentile) or an impressive barrel rate (8.3%, 37th percentile), but he will be moving to a much more pitcher-friendly park when it comes to home runs. Heaney did see a drop in Stuff+, going from 100 in 2023 to 95 in 2024.

Despite that, he posted a solid 3.95 SIERA and 4.18 xFIP, and both represent an improvement in his ERA. Heaney also brings some much-needed stability to the back of the Pirates’ rotation, which will help an area they lacked in last year.