Sweden's Jonas Frogren posted a plus-seven rating at the world championships this past spring. (Paul Chiasson/Canadian Press)

The Toronto Maple Leafs hit a snag Wednesday in their latest dip into the free-agent pool.

They appeared ready to announce the signing of Swedish defenceman Jonas Frogren when the National Hockey League's head office stepped in and rejected the contract.

The league determined Frogren, 28, must be signed to an entry-level deal as a first-year NHL player despite his pro experience in Europe. The Leafs had signed Frogren to a standard contract.

"We are working with the NHL Players' Association to resolve the matter," said Frogren's agent, Don Meehan of Newport Sports. "We remain hopeful it will get resolved."

A physical shut-down blue-liner, Frogren grew up idolizing one-time Maple Leafs defenceman Borje Salming and told Sun Media last week it would be his dream to play in Toronto.

At that time, he confirmed a financial agreement had been reached with Farjestad, his Swedish elite league team.

"He played really well at the world championships," Leafs general manager Cliff Fletcher told the Canadian Press. "He's a physical, defensive defenceman. He can play in our top six next season."

At present, the top six probably consists of Tomas Kaberle, Bryan McCabe, Pavel Kubina, Jeff Finger, Ian White and Carlo Colaiacovo, with Staffan Kronwall, Stralman and perhaps prospect Luke Schenn providing depth.

The six-foot-one, 200-pound Frogren posted a plus-seven rating at the worlds and spent part of the tournament playing alongside Leafs' defenceman Anton Stralman. He has 46 points in 398 games in the Swedish elite league.

Frogren was a teammate of Toronto forward Alex Steen on the Swedish national squad.

With files from the Canadian Press