On Tuesday the White Sox acquired 31-year-old veteran strike-thrower Ivan Nova from the Pirates in exchange for 19-year-old Dominican right-hander Yordi Rosario, and $500,000 in international bonus space.

One of the most efficient strike-throwers in baseball, Nova joins a White Sox rotation comprised mostly of young-ish arms who struggle with walks. White Sox starters who threw at least 100 innings last year posted walk rates between 9% (James Shields) and 13% (Hector Santiago), all of which are below average. Nova’s walk rates have hovered in the 4-5% range during each of the last three seasons, the fifth-best rate in baseball during that span. The White Sox seem to have begun adding veteran pieces to a team that has been rebuilding for a while, perhaps with an eye on competing sooner than later in a weak division that has been dominated by a Cleveland club that appears to be focused more on shedding salary than adding premium talent and further separating themselves.

Nova is in the final year of a three-year deal and is set to make about $9 million in 2019. Pittsburgh’s decision to move him was likely motivated by a combination of the desire to shed salary as well as their comparable in-house replacements for the right-hander, who was a 1.1 WAR pitcher in 2018. The Pirates are stocked with several upper-level sinkerballers who should provide a similar quality of performance until promising pitching prospect Mitch Keller, who we ranked no. 2 in the system, is ready for promotion, which will likely be at some point next year.

The Pirates main return was teenage righty Yordi Rosario, who was advanced enough to garner a 2018 mid-summer promotion from the DSL to the AZL. Rosario is one of four young projection arms acquired by Pittsburgh already this offseason, joining Tahnaj Thomas, Dante Mendoza, and Wilkin Ramos, and he shares several traits with them.

Rosario is a spindly 6-foot-2 and has lots of room on his frame for physical growth, which could lead to increased fastball velocity. He repeats a graceful, athletic delivery and throws a lot of strikes with a fastball that currently resides in the 88-92 range and will bump 93 or 94 on occasion. He also has mature feel for an average, 12-6 curveball that has sufficient depth and bite to miss bats against low-level hitters. We had a 35+ FV on Rosario when the season ended and he’ll slot into the same tier on the Pirates list. His reasonable ceiling is that of a no. 4 or 5 starter, unless he grows into better stuff than I anticipate.

The Luis Robert signing late in the 2016-2017 International Free Agent put the White Sox in the bonus penalty box for the two subsequent signing periods. They’re barred from signing prospects for more than $300,000 until July 2 2019, so their international bonus money is arguably best used in trades like this. What Pittsburgh does with that international bonus space before the current signing period ends in June is undetermined. All of the top IFA talents have signed and the Pirates will be competing for the remaining prospects with teams that lost out on the Victor Victor Mesa sweepstakes, especially Baltimore, which still has several million dollars to spend. Pittsburgh has been more active in Asia than most other clubs.