The Rays' previous record for Opening Day strikeouts was seven, achieved by Steve Trachsel in 2000 and David Price in '11.
Archer allowed three runs -- two earned -- on five hits and three walks. The righty threw 107 pitches, which led to his exit after five innings. He became one of four pitchers to record 12-plus strikeouts on Opening Day and lose, and the first since St. Louis' Bob Gibson lost to the Montreal Expos in 1975.
Archer got off to a rough start when he pitched for 17 minutes in the first, allowing a two-run single to Edwin Encarnacion while throwing 34 pitches.
"He just wasn't locating his fastball," Rays manager Kevin Cash said. "His fastball was a little up in the zone and he was falling behind."
Catcher Hank Conger attributed the long first to Opening Day jitters.
"Because I was amped behind the plate, too," Conger said. "For him, he knows what to do. He's been doing this for a while. I think sometimes if you just try to repeat the same pitch, you know maybe mixing in the curve or the slider here and there, kind of helps him get back on plane. After that first inning, he settled down."
Archer allowed that it was "pretty obvious" that in the first inning he "was a little off."
The right-hander did find his groove though. He appeared close to getting lifted in the fourth. The Blue Jays had already scored in the inning and had runners on first and second with one out. Cash had Enny Romero warming in the bullpen, but Archer recovered to strike out Josh Donaldson and Jose Bautista -- each looking -- to end the threat.
"Stuff was outstanding today," Conger said. "Twelve punchouts. After the first inning you definitely saw him start getting settled down. Get more of a feel for that slider. And then everything was pretty much good from there."
From the third inning through the fifth, Archer's final nine outs were recorded via strikeouts.
"I always want to go more than five innings, but I understand that you can't be perfect every inning, every game," Archer said. "I was happy with how I bounced back, how the team fought back in the end. ... So overall, I wish I could have done a better job in the first inning."
Archer's 12-strikeout, five-inning performance also joined the ranks of the unusual. He became the fourth pitcher since Baseball Reference data became available (1914) to reach 12 strikeouts in an appearance of five innings or shorter, and all of these have happened since 2012.
Others who have turned the trick: Andrew Cashner of the Padres on June 1, 2015, vs. the Mets; Alex Cobb of the Rays on May 10, 2013, vs. the Padres; and Zack Greinke of the Angels on Sept. 25, 2012, vs. the Mariners.
Ironically, as well as Archer has pitched, he is 0-4 in seven starts since the beginning of September, matching the longest losing streak of his career.