In his nine-year career, Jackson has a record of 60-60 with a 4.46 ERA with the Rays, Dodgers, White Sox, D-backs, Cardinals and Tigers. His best moment came on June 2, 2010, when he pitched a no-hitter for Arizona against Tampa Bay.
The Nationals feel Jackson can be a better pitcher by tweaking his delivery. For example, when Jackson pitched from the stretch in 2011, opposing hitters hit .239. When he pitched from the windup, opposing batters had a .339 batting average against him.
"Last year, he was a different pitcher out of the windup than he was from the stretch," Rizzo said. "We feel that there are certain tweaks we can make to his delivery, which will make [the pitches] more difficult to see. If you look at the splits between runners on base and runners not on base, his numbers are really surprising."
Jackson will join a rotation that will include Stephen Strasburg, Jordan Zimmermann and Gio Gonzalez. Before acquiring Jackson, Rizzo felt there was a shortage in the rotation, because Strasburg, who is coming off Tommy John surgery, will be limited to 160 innings. Zimmermann has never pitched a full season in his big league, while Chien-Ming Wang hasn't pitched a full season since 2007, when he was with the Yankees. Wang has missed a lot of time in the past four years because of injuries.
"We felt we had an innings shortage," Rizzo said. "You do the research. Of the eight playoff teams last year, six of those eight teams have two 200-plus-innings pitchers on the team. We felt we had an innings shortage. This not only fixes the innings shortage, but it also gives us a quality standard to compete with anyone in the division."
Rizzo has had interest in acquiring Jackson since 2010. That year, Rizzo tried to trade for Jackson, who was with the D-backs at the time.
With Jackson on the roster, the Nationals will more than likely try to trade left-hander John Lannan for a position player. It's not a secret that Washington is looking for a center fielder for the long term.
On Thursday, the Nats learned that a three-person panel ruled in their favor in the arbitration case against Lannan, who will earn $5 million in 2012.
The arbitration hearing took place in St. Petersburg, on Wednesday morning. Lannan and the Nationals were $700,000 apart, according to The Associated Press. Lannan asked for $5.7 million, while the club offered $5 million.
"We are certainly open to make a deal that makes sense for us -- if it can improve the ballclub," Rizzo said. "We did not acquire Edwin Jackson to trade another starting pitcher in Spring Training or before Spring Training. If a deal comes up that we can't pass up ... we will be open-minded about it. We know we have depth in the rotation. We have good, quality, hard-throwing power pitchers that we are going into camp with.
"If all are healthy and we have an opportunity to make a trade to improve somewhere else, we'll certainly look into it. I like the competition aspect of it. There is going to be a lot of good pitchers out there in Spring Training this year. The best 25 guys will go north."