Indian off-spinner Harbhajan Singh [Images] on Sunday admitted that he was not being able to produce his best bowling so far against England [Images] in the ongoing two-match Test series.

"I am not bowling at my best in this series. Last series I really bowled well," said Harbhajan after he picked just one wicket, conceding 56 runs so far in the second and final Test in Mohali.

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Harbhajan said he would have work on some of the aspects of his bowling to return to his fiery best.

"I am just trying to bowl good line and length. After the match I will try to work on things like seam positioning," he said.

Harbhajan also confessed he had no answer to England captain Kevin Pietersen's [Images] switch-hit shot.

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"I've seen him once hitting to Muralitharan [Images], but you can't do anything about it. He is tremendous," the Punjab bowler said showering praise on Pietersen, who led a spirited England fightback with a superb 144.

"I wish I could hit him with bat," Harbhajan quipped only to add that "I haven't seen many guys batting like this."

About the pitch, Harbhajan said it was getting slower.

"Pitch is getting slower and slower. I have to do my bit now. It (the wicket) was dry after the sun shone today," he said as the fog delayed the start of the third day's play in the morning.