With the San Francisco 49ers trailing the Baltimore Ravens by a 21-6 score at halftime, fans of the team began to speculate on the whereabouts of Alex Smith.

Sophomore quarterback Colin Kaepernick took over the signal-calling duties after Smith suffered a concussion during the regular season, and Kaepernick was kept on the job by head coach Jim Harbaugh even after Smith recovered.

Fans of the 49ers started to question Harbaugh’s decision to play Kaepernick over Smith on Twitter toward the end of the first half of the Super Bowl, as the score grew a bit lopsided.

“Where's Alex Smith?? now thats the question of the night #SuperBowl,”@DJNARESH wrote.

@MikeyG_23 tweeted, “D---it Kaepernick, where's Alex Smith again ... this isn't good at allll.”

@BrianOkicks shared: “Where's Alex Smith? Kapernick is out of his element.”

@DanBrownII said, “The fact that 'Where's Alex Smith?' is trending shows Kaepernick's performance.”

Meanwhile, @ElmiBTechmen came up with an answer to everyone’s question: “‘Where's Alex Smith at?!’ Why are you asking for Alex Smith when your AVI is kapernick.”

Fans of the Ravens fans appeared to find humor in the opposing supporters questions concerning the whereabouts of Smith.

@AntLeeTaylor laughed: “lol. #49ers getting mad. where's Alex Smith?”

@I_am_VocalImage joked: “Great pass....wrong person though. Where's Alex Smith? Just kidding!!”

And @BrooklynKid187 made fun of those questioning where Smith was during the Super Bowl: “This Kaepernik guy is a star. Where's Alex Smith #AmberAlert lol.”

Harbaugh -- Jim Harbaugh -- is surely going to endure the brunt of the criticism should the 49ers lose, as many, on and off Twitter, will likely argue that Kaepernick couldn’t handle the pressure of the Super Bowl as well as Smith would have.