BSkyB vowed to carry out its threat to fight the ruling through the courts, hiring high powered City law firm Herbert Smith.
The decision means the wholesale prices Sky is allowed to charge rivals including BT and Virgin have been slashed.
Furious Sky chief executive Jeremy Darroch, said: “We think they’ve got it badly wrong. The prices we charge are fair, they’re fair for customers and they’re fair for the companies that we supply our channels to.
“I think Ofcom’s decision is likely to hit British sport where it hurts.”
His views were echoed by the main football, rugby and cricket boards, which fear their revenues will be rocked by the decision.
Premier League chief executive Richard Scudamore said: “The Premier League is at one with the rest of UK sport over Ofcom’s ill-judged and disproportionate intervention in the broadcast market.
“Its action will strip out competition for sports rights and hugely reduce the incentives of all bidders, Sky included, to invest in sports rights.”
Even Sky’s rivals, including BT, which will sell Sky’s wholesale package for the first time, described the announcement as disappointing.
They claim the ruling gives Sky “wriggle room” to dodge some of the effects of the ruling and say the prices are still too high to allow them to compete with the broadcaster.
Gavin Patterson, chief executive of BT Retail, said: “Ofcom should have gone much further than it did.”
Virgin Media chief executive Neil Berkett said: “It’s disappointing that some significant loopholes remain which provide an opportunity for Sky to further undermine competition.”
Analysts believe Ofcom forced through the legislation in the knowledge that a Tory government would restrict its role to an industry watchdog rather than a legislator.
HERBERT Smith competition partner Stephen Wisking is advising long standing client Sky on its battle with competition watchdog Ofcom.
Wisking has advised the broadcaster numerous times in the past, including proceedings relating to its exclusive Premier League television contracts.
Other notable work for Wisking includes, acting for Vodafone in relation to Competition Appeal Tribunal proceedings brought by Floe Telecom, Time in relation to its acquisition of IPC Media and Andersen UK on obtaining European merger clearance for its deal with Deloitte.
Although Ofcom turned to its in-house legal team in the Sky matter, City firm Ashurst has taken a role advising Virgin Media, under the lead of partner Duncan Liddell.
Ashurst remains close adviser to Virgin Media and recently acted for the media giant before the Court of Appeal in connection to Sky’s acquisition of 17.9 per cent of ITV.
Former Sky press chief Tim Allan, has been advising BT Vision on its media and lobbying strategy.