CHICAGO -- The White Sox offense for the 2018 season already has benefited from an opportunistic front office, and the team has yet to take the field.
That opportunistic nature centers, in this case, on catcher Welington Castillo joining the White Sox via free agency at the start of December on a two-year, $15 million deal with an $8 million club option for 2020. The 30-year-old provides a steady influence in the lineup and behind the plate, making him a good addition even during the talent development phase of this ongoing rebuilding process.
Castillo looks to be the only change from the lineup that finished the 2017 campaign, although the team should have a healthy Charlie Tilson back competing for time in center this season.

MLB.com is taking a look at the projected lineup of all 30 teams ahead of Spring Training. Here's how the White Sox might stack up:
LINEUP IF SEASON STARTED TODAY
Tim Anderson, SS
Yoan Moncada, 2B
Jose Abreu, 1B
Avisail Garcia, RF
Welington Castillo, C
Nicky Delmonico, LF
Yolmer Sanchez, 3B
Matt Davidson, DH
Adam Engel, CF
STRENGTH
Everyone with the White Sox waited patiently for Garcia to develop into the five-tool sort of talent they envisioned, and that patience was rewarded with Garcia's first All-Star appearance in 2017, when he finished with the third-highest batting average in all of baseball at .330. Abreu has been an elite run producer since arriving with the White Sox, and with the addition of Castillo's power, the South Siders have a solid middle of the order. They have flexibility with players such as Moncada and Anderson, who could hit high in the order but also are able to move lower and drive in runs.

QUESTION MARK
Chicago's lack of a true left-handed power hitter helped stoke Hot Stove talk of a hypothetical match between the White Sox and free-agent third baseman Mike Moustakas. Delmonico is the only true left-handed hitter in this version of the lineup, although Moncada and Sanchez are both switch-hitters. The team also needs greater production from Engel, who matches any center fielder in the American League defensively but needs to improve on the .166 average and 117 strikeouts against 19 walks he compiled in his debut season. The offense leans toward the free-swinging side, ranking 11th overall in strikeouts, 28th in walks and 25th in on-base percentage in 2017.

WHAT MIGHT CHANGE
Abreu and Garcia are the most valuable trade pieces on the roster, but the White Sox hold two years of contractual control on each, so there's certainly no rush to make a final decision about any potential moves. Opposing teams might not be able to match the high value the White Sox place on the young stars, on and off the field.
• Hot Stove Tracker
General manager Rick Hahn has talked about being opportunistic in Year 2 of the rebuild, as the Castillo signing and the team's interest in acquiring Manny Machado from Baltimore exhibits. But the White Sox will do nothing to subtract from the long-term goal of achieving sustained success and becoming a regular World Series contender.
Casey Gillaspie, the team's No. 11 prospect per MLB Pipeline, will challenge for designated hitter at-bats. Switch-hitter Leury Garcia and the left-handed hitting Tilson also are center-field options.