But the gesture, intended to heal internal divisions, did not seem to be paying off. Reinhard Klimmt, the closest political ally of Oskar Lafontaine, immediately announced that he would continue to fight his government's economic reforms.
"My position is no different from what it was," Mr Klimmt declared at a joint appearance with the Chancellor. He said he would oppose the government programme in parliament's upper chamber, the Bundesrat, during his remaining weeks as Prime Minister of Saarland.
After that, he would submit to cabinet discipline, but still continue to fight his corner. "It must be possible to have differing positions in the same party," he declared.
Mr Klimmt is taking over the transport and construction portfolio left vacant by the promotion of its right-wing incumbent, Franz Muntefering, to a powerful new post at the head of the party apparatus. Mr Muntefering's job is to impose some kind of order on the Social Democrats, whose opposition to the Chancellor's policies has been growing louder.
The divisions have contributed to the governing party'sstring of catastrophic defeats in regional elections. Mr Klimmt is the most recent victim, losing power in Saarland on Sunday.
Before those elections, he had lambasted the "unfair" austerity programme of the federal government, and vowed to vote against it later this month in the Bundesrat, where the coalition lacks a majority.
A few days later, he will don a cabinet hat. Mr Schroder said he was sure his new minister would display the quality he valued most among his colleagues: loyalty.
Certainly, the Saarlander has shown abundant loyalty to his mentor, Mr Lafontaine, the left-wing former finance minister and party chairman. It was to him, after all, that he owed his previous job.
Mr Lafontaine had handed it to him when he entered Mr Schroder's government last year. Since then, Mr Klimmt has played the part of a Lafontaine clone to perfection, down to the accent - he actually comes from Berlin - body language and political vocabulary.
Yesterday, he said he saw no contradiction in his new role, since his ministry would not be affected by welfare cuts imposed in the Budget. The Chancellor, sitting next to him and looking as though he had swallowed a lemon, remarked that cabinet discussions on the Budget were closed.
With Mr Lafontaine plotting a comeback, Mr Schroder seems to have calculated that he'd rather have a clone than have the real thing snapping at his heels.