The Slovenia Under-21 international has joined on a free transfer after leaving Italian side Ascoli.
The 20-year-old came through Milan's youth academy and spent a month on loan with Leeds in 2014-15, making two appearances as a substitute.
Benedicic has also played for Serie B side Como and featured nine times for Ascoli before leaving.

The item was sold to a private Irish collector.
It was part of a sale of over 600 items, many from the 1916 Rising.
The rebellion was an attempt to overthrow British rule 100 years ago.
The 1916 proclamation is considered one of the most important documents in Irish history.
Auctioneers said that the copy was from Dr James Ryan, a medical officer attached to the garrison based out of the General Post Office (GPO) during the Easter Rising.
The GPO was the headquarters of the Rising's leaders.
After the GPO was taken by rebel forces, Pádraig Pearse, the Rising's comander-in-chief, read the proclamation from the front of the building.
The seven signatories of the proclamation were executed, along with nine other leaders, after the Rising was quelled.
Last month, hundreds of thousands of people lined the streets of Dublin for a parade to mark the Easter Rising's centenary.
The 1916 Proclamation was then read out by an officer from the Irish defence forces during the parade, in a re-enactment of the declaration of independence the rebels made outside the GPO.

The drones were designed to bring the internet to remote rural areas, complementing its Loon project - a similar initiative using hot air balloons.
However, the solar-powered vehicles have faced technical difficulties and funding challenges.
On Wednesday, blog 9to5 Google revealed Titan had actually shut in early 2016.
A statement from X, the Google division responsible for Titan, confirmed the news.
"Titan was brought into X in late 2015. We ended our exploration of high altitude unmanned aerial vehicles for internet access shortly after," it said.
"By comparison, at this stage the economics and technical feasibility of Project Loon present a much more promising way to connect rural and remote parts of the world."
Google acquired Titan Aerospace in 2014, reportedly fending off a bid from Facebook, which has also been trialling internet-providing drones.
At the time Google said it was "early days", but that "atmospheric satellites could help bring internet access to millions of people, and help solve other problems, including disaster relief and environmental damage like deforestation".
However, after test flights began in 2015, reports alleged that Titan was facing technical difficulties and was running out of money.
In mid-2015, the Titan team also experienced a crash in the Arizona desert which was later linked to a wing fault.
The statement added that "many" Titan staff had been reassigned to different parts of the business, including Project Loon and Wing, a division dedicated to providing drone-based deliveries.
Facebook's internet drones have also faced problems.
The firm's Aquila drone crashed during a test flight in June, prompting an investigation by the National Transportation Safety Board, and an explosion destroyed one of its satellites earlier in 2016.

Both Broughty Ferry lifeboats were called out shortly before midday, with a Coastguard helicopter later joining the search.
Coastguard officers conducted a search on foot of the waterfront area close to the bridge.
The lifeboats were stood down at about 15:00.
A Broughty Ferry RNLI spokesman said: "The inshore lifeboat was launched within six minutes and was quickly in the area of the reported sighting.
"The all-weather lifeboat Elizabeth of Glamis was launched a short time later to join the search.
"Following an extensive search of the area no one was found."
Leyton Orient have signed former Leeds and AC Milan midfielder Zan Benedicic on a deal until January.
[NEXT_CONCEPT]
An original copy of the Irish proclamation, that was reputedly hung in the headquarters of the rebel leaders during the Easter Rising, has sold at an auction in Dublin for 150,000 euros (£117,000).
[NEXT_CONCEPT]
Google has confirmed it has closed its internet drone project Titan, three years after it bought the business.
[NEXT_CONCEPT]
A lifeboat and Coastguard search has been carried out after a report of a body seen in the water near the Tay Road Bridge at Dundee.