Erling Haaland was only substituted as a precaution in Borussia Dortmund's 4-2 Klassiker defeat to Bayern Munich, interim coach Edin Terzic said.
Superstar striker Haaland looked to have set BVB on course to a fine victory when he netted twice in the opening nine minutes at the Allianz Arena on Saturday.
Those efforts took his tally against Bayern this season to four goals across all competitions, the most in matches with the Bavarian giants over the course of a single campaign since Cristiano Ronaldo netted five in 2016-17.
But by the time Haaland made way after 60 minutes, nursing a cut to his ankle, Bayern were back level.
Robert Lewandowski scored twice before the break and then, following Haaland's departure, a crucial, controversial Leon Goretzka volley preceded the home forward's hat-trick goal.
Images of Haaland wincing in pain on the bench were unlikely to lift the mood among Dortmund supporters, already unable to watch Jadon Sancho following a muscle injury in midweek.
Yet Terzic said Haaland, now with 19 league goals to his name at a rate of one every 84 minutes this term, was merely being protected.
BVB host Sevilla in the Champions League on Tuesday, aiming to protect a 3-2 first-leg advantage, with Haaland set to start for the 28th time this season.
"He played a very good game," Terzic said. "He got a little kick, but that wasn't the problem.
"He's been playing every game for weeks; we've got to protect him a little bit. We expect him to be able to play against Sevilla."
Haaland's double took him to 32 Bundesliga goals across 34 matches this season and last.
Uwe Seeler is the only player in the history of the competition to score more often in his first 34 appearances (33).