Dayton was also honored in the voting for coach of the year. Anthony Grant led the third-ranked Flyers to a 29-2 record in the regular season and a perfect 18-0 mark in the conference.
"It means our guys had a really good year," Grant said. "It means our staff did an outstanding job. There are a lot of people that I have to thank for the recognition."
That was only the second honor of the day for Grant, who was named the national coach of the year by The Sporting News on Tuesday morning.
» NCAA TOURNAMENT PICTURE: Flyers in hunt for No. 1 seed
Grant is the third UD coach to win A-10 honor. Archie Miller won it in 2017 when Dayton won the outright championship for the first time. Oliver Purnell was honored in 1998.
Dayton’s Jalen Crutcher, who made the second team last season, joined Toppin on the first team. This is the first time Dayton has had two first-team selections.
Dayton's Obi Toppin reacts to A-10 award news
Dayton's Anthony Grant reacts to A-10 awards
"I try not to get into individual awards," Crutcher said, "but it's really great that everyone voted me to the first team."
Dayton’s Trey Landers made the A-10 third team, and Ryan Mikesell made the all-academic team.
"We're really proud of what those guys were able to accomplish," Grant said, "and the recognition they received from the coaches in the league is really gratifying."
Rhode Island's Fatts Russell, Richmond's Jacob Gilyard, St. Bonaventure's Kyle Lofton and Saint Louis' Jordan Goodwin joined Toppin on the first team. Tre Mitchell, of UMass, was named the league's top rookie.
AJ Wilson, of George Mason, won the Chris Daniels Most Improved Player Award. Javonte Perkins, of Saint Louis, was named sixth man of the year. Richmond's Jacob Gilyard was named the league's top defender.
More awards could be on the way for Toppin. He was named a first-team All-American by ESPN's Dick Vitale on Sunday. Rob Dauster, of NBC Sports, named Toppin his national player of the year on Monday.
“What makes Toppin so special,” Dauster wrote, “is that it is his unique combination of skills that allows Dayton to be able to play the way that they want to play. He has the size, strength and athleticism to be able to guard basically any position on the floor, giving the Flyers the ability to play a switching defense. Then combine that with the way that he can play on the perimeter, his ability as a passer and playmaker, his elite floor-running and the fact that he is the most dangerous player in college basketball rolling to the rim after a ball-screen, and what you get is the nation’s most dangerous offense.
Third-ranked Dayton (29-2) has the top seed in the A-10 tournament and will play No. 8 seed Massachusetts or No. 9 Virginia Commonwealth in the quarterfinals at noon Friday at the Barclays Center in Brooklyn, N.Y.
Dayton's Jalen Crutcher reacts to A-10 awards