In 2009 Kelly signed a minor league contract with an invitation to spring training with the Tigers.
Following spring training Kelly rejoined the Mud Hens, with whom he had last played in 2006.
On June 11, 2009, the Tigers called Kelly up to the Major League club to replace outfielder Clete Thomas.
Kelly played his first game for Detroit against the Pittsburgh Pirates, his former club.
After going hitless in his first game, he hit a two-RBI single and a double against Pittsburgh, obtaining his first major league extra base hit and RBIs.

On October 1, 2010, Kelly hit a home run in both games of a doubleheader against the Baltimore Orioles.

In his first two seasons with the Tigers, Kelly added first and third base and center field to the positions he has played in the majors.
He was called on to pitch with two outs in the top of the ninth inning after manager Jim Leyland thoroughly depleted his bullpen in a 16–9 defeat to the New York Mets at Comerica Park on June 29, 2011.
Throwing only five pitches, he used a curveball to get Scott Hairston to fly out to center field.
Kelly was the first position player to pitch in a game for the Tigers since Shane Halter did it in October 2000.
He reached the milestone of having played every position on the field in his major league career in a 15–3 loss at home to the San Francisco Giants three nights later on July 2.
He entered the contest at the start of the fourth inning, replacing starting catcher Víctor Martínez who had left the game with a bruised right shoulder.

In the decisive Game 5 of the 2011 American League Division Series against the New York Yankees, Kelly belted a first-inning solo home run off Iván Nova into the right field seats at Yankee Stadium to give the Tigers a 1–0 lead, one which they never relinquished.
Detroit went on to win the game, 3–2, and moved on to face the Texas Rangers in the American League Championship Series.

On August 3, 2012, Kelly was designated for assignment to make room on the 40-man roster for outfielder Andy Dirks, who returned to the Tigers after coming off the disabled list the same day.
On August 9, 2012, Kelly cleared waivers and his contract was outrighted by Detroit to their Triple-A affiliate Toledo.
The Tigers called him up again on September 1, and later named him to their post-season roster after the team clinched the AL Central division.
He hit a walk-off sacrifice fly in Game 2 of Detroit's American League Division Series against the Oakland Athletics.

On October 31, 2012, Don Kelly cleared waivers and became a free agent.
 On January 16, 2013, Kelly signed a minor league deal with the Tigers.
He made the team out of spring training, and played another full season as the club's super-utility man.
In 216 at-bats, Don hit .222 with six home runs and 23 RBIs, while playing six defensive positions.
After the season, Kelly signed a one-year deal with Detroit that would pay him $1 million in 2014, avoiding arbitration.
On November 3, 2014, Kelly declined his minor league assignment and became a free agent.
In 2009 Kelly signed a minor league contract with an invitation to spring training with the Tigers. Following spring training Kelly rejoined the Mud Hens, with whom he had last played in 2006. On June 11, 2009, the Tigers called Kelly up to the Major League club to replace outfielder Clete Thomas. Kelly played his first game for Detroit against the Pittsburgh Pirates, his former club. After going hitless in his first game, he hit a two-RBI single and a double against Pittsburgh, obtaining his first major league extra base hit and RBIs.
On October 1, 2010, Kelly hit a home run in both games of a doubleheader against the Baltimore Orioles.
In his first two seasons with the Tigers, Kelly added first and third base and center field to the positions he has played in the majors. He was called on to pitch with two outs in the top of the ninth inning after manager Jim Leyland thoroughly depleted his bullpen in a 16–9 defeat to the New York Mets at Comerica Park on June 29, 2011. Throwing only five pitches, he used a curveball to get Scott Hairston to fly out to center field. Kelly was the first position player to pitch in a game for the Tigers since Shane Halter did it in October 2000. He reached the milestone of having played every position on the field in his major league career in a 15–3 loss at home to the San Francisco Giants three nights later on July 2. He entered the contest at the start of the fourth inning, replacing starting catcher Víctor Martínez who had left the game with a bruised right shoulder.
In the decisive Game 5 of the 2011 American League Division Series against the New York Yankees, Kelly belted a first-inning solo home run off Iván Nova into the right field seats at Yankee Stadium to give the Tigers a 1–0 lead, one which they never relinquished. Detroit went on to win the game, 3–2, and moved on to face the Texas Rangers in the American League Championship Series.
On August 3, 2012, Kelly was designated for assignment to make room on the 40-man roster for outfielder Andy Dirks, who returned to the Tigers after coming off the disabled list the same day. On August 9, 2012, Kelly cleared waivers and his contract was outrighted by Detroit to their Triple-A affiliate Toledo. The Tigers called him up again on September 1, and later named him to their post-season roster after the team clinched the AL Central division. He hit a walk-off sacrifice fly in Game 2 of Detroit's American League Division Series against the Oakland Athletics.
On October 31, 2012, Don Kelly cleared waivers and became a free agent.  On January 16, 2013, Kelly signed a minor league deal with the Tigers. He made the team out of spring training, and played another full season as the club's super-utility man. In 216 at-bats, Don hit .222 with six home runs and 23 RBIs, while playing six defensive positions. After the season, Kelly signed a one-year deal with Detroit that would pay him $1 million in 2014, avoiding arbitration. On November 3, 2014, Kelly declined his minor league assignment and became a free agent.
Don Kelly (baseball)