Bayern's new 23 million-euro (31.4 million-dollar) strikeforce gave their employers an instant return as Toni netted, before German striker Miroslav Klose, a 12-million-euro signing from Werder Bremen, scored twice in Saturday's second-half.

The German giants's 69 million euros summer spending spree was rewarded after just 14 minutes as Klose drew the Hansa goalkeeper for Toni, who signed from Fiorentina for 11 million euros, to knock the ball into an empty net.

Hitzfeld admitted he took a big gamble to play Toni, 30, who damaged knee ligaments in a pre-season game last month and only trained with the Bayern team last Thursday.

"I am pleased that the risk came off to play Luca Toni," said Hitzfeld.

"I thought about it long and hard before I selected him.

"He only trained two weeks ago after recovering from his knee injury and he only trained with the team for the first time on Thursday.

"I thought he might struggle, but he blended in well and was strong.

"He is a big man who can block and present the ball very skillfully.

"I could see that his presence let Klose play his own game, so the risk was worthwhile."

Bayern's 4-3 win on penalties over third-division minnows Wacker Burghausen in the first round of the German Cup the week before had been the perfect wake-up call and Hitzfeld was pleased his side were fired up.

"I think we made a good start against Rostock," said Hitzfeld.

"We had a warning at Burghausen when we saw it can be so easy to lose if you don't concentrate properly and Rostock have won three times at Munich.

"That really motivated the team and focused minds, so we started very well.

"We deserved the 1-0 lead at half-time, but Rostock had four or five chances to counter-attack, which they did not finish.

"The fact they had chances did not please me at all and that is something we have to work on.

"We let them have far too much free space after our attacks and we were badly organised, that is something we have to improve.

"Things weren't so simple for us after the break, the 2-0 lead came late in the game, but our defence was very strong.

"People will talk about our forwards, but our defenders all played well and contributed to the attacks.

"Ze Roberto and Mark van Bommel did well in midfield."

Hitzfeld reserved special praise for French midfielder Franck Ribery who was dynamic in attack and battled for every scrap of possession he could get his boot to.

Having injured a knee in Bayern's successful German League Cup campaign, Hitzfeld pulled his 26-million-euro signing off in the second-half to preserve him for this week's games against Barcelona and Werder Bremen.

"Franck is a constant source of energy and covers every blade of grass, he is aggressive and he did well before we pulled him off in the second-half, he was feeling the effects of his leg injury and I didn't want him to aggrevate it."