The 20-year-old, who has scored 12 goals for club and England Under-21s this year, is expected to put pen to paper on a new deal imminently.
"It'll be great for Saido first and foremost, he's a young boy and maybe he's become a little bit distracted by the fact that it's been going on for so long," The Mirror quotes Clarke as saying.
"That's been a little negative - but there's not too many negatives surrounding Saido this season. He's been a breath of fresh air in the squad and a revelation.
"When he signs his contract, he's got a massive part to play over the rest of the season for us. The next stage is for him to keep doing what he's been doing and try to improve. He can start games, he doesn't have to worry about that."
Arsenal and Chelsea were thought to be monitoring Berahino.