The seven-player became official after the Jays and Dickey agreed to a three-year contract extension Monday.
Heading with d'Arnaud to New York are right-hander Noah Syndergaard, veteran backstop John Buck and Minor League outfielder Wuilmer Becerra. Dickey is heading to Toronto along with catchers Josh Thole and Mike Nickeas.
d'Arnaud -- whom the Blue Jays acquired for another Cy Young Award winner, Roy Halladay, in 2009 -- is MLB.com's No. 11 overall prospect. The 23-year-old hit .333 with 16 homers and 52 RBIs in 67 games with Triple-A Las Vegas before a torn knee ligament ended his 2012 season in June.
While power numbers in the Pacific Coast League deserve close scrutiny, d'Arnaud had a breakout year with Double-A New Hampshire in 2011, batting .311/.371/.542 with 21 homers and 78 RBIs in 114 games. A first-round pick (37th overall) by the Phillies in 2007, d'Arnaud turns 24 in February and is considered a strong defender, throwing out 30 percent of potential basestealers in the PCL.
Syndergaard also was a first-round pick, going 38th overall in 2010. In his first full season as a pro, he went 8-5 with a 2.60 ERA in 27 games, including 19 starts, for Class A Lansing and climbed to No. 38 on MLB.com's list of Top 100 Prospects. The 6-foot-5 Texan, who turned 20 in late August, struck out 122 batters, walked 31 and allowed three home runs over 103 2/3 innings. He held opponents to a .212 average and was named a Midwest League midseason All-Star.
Syndergaard boasts a fastball in the upper 90s and showed good command for a 19-year-old this season. His curve and changeup are potentially above-average offerings.
While Syndergaard likely would start the 2013 campaign with the Mets' Class A Advanced affiliate in St. Lucie, the potential loss of Dickey creates an opportunity for other prospects to join the big league rotation.
At the top of that list is Zack Wheeler, who excelled across two levels this year but has made only six appearances above Double-A. Jeurys Familia, the Mets' No. 2 prospect, was less impressive but has the edge in experience with 28 Triple-A starts and eight Major League appearances. Familia has struggled with his command, however, finishing third in the International League with 73 walks over 137 innings this season.