The 25-year-old is an outfielder by trade but may have to prove he is capable of playing at least one other position in an emergency situation to hold down a spot on the roster.
"We wanted to look at it a little bit," Blue Jays manager John Gibbons said. "If we got in a pinch, could he do it? How much he'll play? I wouldn't anticipate seeing a whole lot of it, but we're looking at it.
"He doesn't look too bad out there, but that's practice. Normally, everyone looks good in practice. When the game speeds up, it's a different story. But we'll see; he doesn't look too bad."
Gibbons seemed skeptical about Sierra's abilities at first but is at least keeping an open mind. The Blue Jays already have Edwin Encarnacion and Adam Lind available at the position, but whoever doesn't start there will usually get the nod at designated hitter.
That's why the Blue Jays would like to increase Sierra's versatility. If either Encarnacion or Lind had to come out of the game the club could turn to Sierra instead of losing the DH. It's not an ideal situation but is something the club hopefully won't have to do very often.
Sierra is an early favorite to earn a job in part because of his contractual status. The club still sees some upside in his bat, and he has been mentioned as a potential platoon partner with Lind at DH when there is a left-handed pitcher on the mound.
The Dominican native is a career .252 hitter with a .725 OPS in 84 games at the big league level. He regained a favorable status in the organization after he was called up as an injury replacement late in the 2013 season and proceeded to record 15 extra-base hits in just 107 at-bats.
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. This story was not subject to the approval of Major League Baseball or its clubs.