Don Mattingly was a beloved captain of the New York Yankees during the 1980s and early 1990s but now finds himself in a new role as coach of their division rivals Toronto Blue Jays. While some fans may be upset to see Mattingly in a different uniform, Blue Jays fans are having a field day.Mattingly, a six-time All-Star first baseman, spent his entire playing career with the Yankees from 1982 to 1995. He was a fan favorite and one of the best players of his era but never won a World Series ring. Mattingly retired in 1995 and was inducted into the Yankees' Hall of Fame in 1997.After his playing career ended, Mattingly became a coach and worked his way up through the Yankees' organization. In 2008, he was promoted to the management staff as their hitting coach and helped them win the World Series that year. In 2011, he was hired as the manager of the Los Angeles Dodgers.Mattingly managed them for five seasons, winning three division titles and making two National League Championship Series appearances. He left the Dodgers after the 2015 season and was hired as the manager of the Marlins. He led a young Marlins team to a surprising playoff appearance in 2020. Mattingly's departure from the Marlins was seen as a surprise, but his arrival in Toronto has been greeted with enthusiasm by Blue Jays fans. After a video of Don Mattingly during the Blue Jays photo day was released on Twitter, many fans were eager to take a dig at their rivals. One tweeted: "Looking good. Tide took those ugly pinstripes right out!" Another wrote:"Glad to see he’s representing the right team now."Here are some of the other reactions:Toronto Blue Jays@BlueJaysDonnie Baseball looks better in Blue 🤩 #PhotoDay166085Donnie Baseball looks better in Blue 🤩 #PhotoDay https://t.co/HPSgKR8qJ1David Vassegh@THEREAL_DV twitter.com/bluejays/statu…Toronto Blue Jays@BlueJaysDonnie Baseball looks better in Blue 🤩 #PhotoDay4085Donnie Baseball looks better in Blue 🤩 #PhotoDay https://t.co/HPSgKR8qJ1🇨🇦 twitter.com/bluejays/statu…shano_808@shano_808Don Mattingly doing his thing.. can you blame him? I sure won’t because the Yankees are the losers for this even becoming a thing twitter.com/bluejays/statu…Toronto Blue Jays@BlueJaysDonnie Baseball looks better in Blue 🤩 #PhotoDay185Donnie Baseball looks better in Blue 🤩 #PhotoDay https://t.co/HPSgKR8qJ1Don Mattingly doing his thing.. can you blame him? I sure won’t because the Yankees are the losers for this even becoming a thing twitter.com/bluejays/statu…Jonah 🇨🇦🇵🇭@jonah_nvJust remembering how he was a terror at the plate against Toronto in the 80s. This is a sight to behold twitter.com/BlueJays/statu…Toronto Blue Jays@BlueJaysDonnie Baseball looks better in Blue 🤩 #PhotoDay585Donnie Baseball looks better in Blue 🤩 #PhotoDay https://t.co/HPSgKR8qJ1Just remembering how he was a terror at the plate against Toronto in the 80s. This is a sight to behold twitter.com/BlueJays/statu…Kevin Parker@kparker4444@BlueJays @jaankeess Looking good. Tide took those ugly pinstripes right out!1@BlueJays @jaankeess Looking good. Tide took those ugly pinstripes right out!Greg Elgie@GregElgie@BlueJays @MLB @MLBNetwork @Sportsnet @FAN590 One of my favourite players growing up even though be played for the wrong team. Glad to see he’s representing the right team now.1@BlueJays @MLB @MLBNetwork @Sportsnet @FAN590 One of my favourite players growing up even though be played for the wrong team. Glad to see he’s representing the right team now.VioletBrown@Brown01VioletI am not sure I'll ever get used to this but I'm liking what I see so far twitter.com/BlueJays/statu…Toronto Blue Jays@BlueJaysDonnie Baseball looks better in Blue 🤩 #PhotoDay166085Donnie Baseball looks better in Blue 🤩 #PhotoDay https://t.co/HPSgKR8qJ1I am not sure I'll ever get used to this but I'm liking what I see so far twitter.com/BlueJays/statu…⭐️Dan⭐️@265KilometresThis looks weird, I'm not gonna lie twitter.com/BlueJays/statu…Toronto Blue Jays@BlueJaysDonnie Baseball looks better in Blue 🤩 #PhotoDay185Donnie Baseball looks better in Blue 🤩 #PhotoDay https://t.co/HPSgKR8qJ1This looks weird, I'm not gonna lie twitter.com/BlueJays/statu…OBird2023@Bird2023O@BlueJays @MLB @MLBNetwork @Sportsnet @FAN590 Donnie has a chance to win.@BlueJays @MLB @MLBNetwork @Sportsnet @FAN590 Donnie has a chance to win.Ballin Beavers ⚽️🏀⚾️@TopTierBeavers@BlueJays @MLB @MLBNetwork @Sportsnet @FAN590 WE LOVE TO SEE IT@BlueJays @MLB @MLBNetwork @Sportsnet @FAN590 WE LOVE TO SEE ITYankees legend Don Mattingly set to take Blue Jays to new heightsThe Toronto Blue Jays are coming off a strong season, finishing with a 91-71 record and narrowly missing the playoffs. With a talented young core that includes Vladimir Guerrero Jr. and Bo Bichette, the Blue Jays are expected to be contenders in the MLB for a while.With Mattingly now on board as coach, the Blue Jays will have even more experience and leadership in their dugout. Whether he can help them beat the Yankees remains to be seen, but one thing is for sure: the rivalry between the two teams has just got a bit more interesting.