Smyly, who began the spring with nine scoreless innings in his first three starts, has given up seven earned runs in his last two outings, including five in Sunday's 12-10 loss to the Washington Nationals.
Ross Detwiler started for Washington in his first game back since pitching for the United States in the World Baseball Classic. He allowed three hits and a run in four innings on a long homer by Torii Hunter in the first.
Smyly is competing with Rick Porcello for the final spot in the rotation behind Justin Verlander, Anibal Sanchez, Doug Fister and Max Scherzer. Porcello hasn't walked a batter all spring and has a 2.50 ERA.
After giving up five earned runs in four innings against the Nationals, Smyly said he simply had to work on keeping the ball down.
"I just struggled with everything," he said. "I kept the ball up and I can't do that. Let's just put it this way: They got me good."
Smyly was 4-3 with a 3.99 ERA in 23 games, including 18 starts, for the Tigers last season. He knows there's only room for five starters in Detroit's rotation, and nothing is assured even though he started off so well.
"It doesn't matter what I did earlier in the spring," Smyly said. "Nothing matters except your last start."
Tigers manager Jim Leyland was succinct about the left-hander's performance.
"(Smyly) got the ball up and he had to pay the price," Leyland said. "He can't do that."
The Tigers gave up the most runs they have allowed all spring, but Leyland wasn't going to make a scapegoat of Smyly.
"I saw a lot of things I didn't like today," Leyland said. "It had nothing to do with the starting pitcher. Our bullpen didn't do the job. It had nothing to do with the starter."
Al Alburquerque, a candidate for the closer role, allowed four runs in two-thirds of an inning while walking three. Duane Below, looking for a job in Detroit's bullpen, has a 12.38 ERA after giving up two earned runs in one inning.
Detwiler said he felt fine after his four innings despite allowing the long home run to Hunter.
"I only really missed on one pitch and that was the home run to Hunter," Detwiler said. "It was a bad pitch and he didn't miss it. Other than that I felt fine."
Matt Tuiasosopo homered and knocked in two runs for the Tigers. He also scored three times.
Nationals C Jhonatan Solano played left field for two innings when Micah Owings was lifted with a sore quadriceps. ... Jordan Zimmermann will start Monday in Viera against Tigers RHP Max Scherzer. ... Detroit OF Quintin Berry walked and scored a run, then was removed from the game. He has been struggling with patellar tendinitis. ... Scherzer has pitched 8 2/3 innings in three starts this spring. He has struck out 14 without allowing a run. ... Sanchez will start a minor league game in Lakeland on Monday against an Atlanta Braves affiliate. ... RHP Octavio Dotel is the only Tigers player remaining in the World Baseball Classic.