The second half was “characterised by uncertainty again”, he said. “It was a bit slapstick.”
Bayern were hamstrung by the dismissal of Dayot Upamecano, who was shown a red card for crashing into Gustav Isaksen in the penalty area.
Immobile stepped up to score the resulting spot-kick.
“We made a lot of individual mistakes and we conceded a penalty and red card from out of absolutely nothing,” Tuchel said in the post-match press conference.
“With the performance we did everything to lose this game, which was completely in our hands.”
The defeat in Rome follows the 3-0 reverse against Bayer Leverkusen which leaves Bayern five points off the pace in the Bundesliga title race.
But asked if he feared for his job, Tuchel said simply: “No”
© Agence France-Presse
Photo: Twitter @StatmanDave