Sky Sports have agreed a five-year broadcast deal with the Scottish Premier League that will also include coverage of Rangers in the third division.

Herald Sport understands that the deal is worth around £14m a season and contains no clauses regarding the return of the Ibrox side after one year. The contract is based on the assumption that Rangers will work their way back up the leagues, and so not returning to the SPL until the 2015/2016 season at least.

The deal is worth around £2m per season less than the contract the SPL had previously agreed with Sky and which was due to begin this season, but there is less of a reduction than many clubs feared because Sky considers Rangers' games in the SFL as an additional product.

The SPL had to pay a fee to their counterparts for that access – thought to be around £1m. The top-flight clubs have still to ratify the deal, but that is expected to be a formality that will be signed off on Friday. Sky will broadcast 30 live SPL games this season, starting with Celtic v Aberdeen at 12.45pm on Saturday.

Sky will also show five of Rangers' league games live, beginning with their first game in the third division, away to Peterhead on August 11 at 12.45pm.

"We've supported Scottish football since we started, over 20 years ago, and have always wanted to continue that commitment," said Barney Francis, managing director of Sky Sports. "Our viewers will see the SPL for five more years and our schedule includes the opening league match for Celtic. We will also follow Rangers as they plot their way back to Scottish football's top flight. Clubs now have certainty over their income and exposure across the UK and Ireland and we look forward to the new season."

There had been fears that Sky would reduce their financial commitment more drastically, and that some SPL clubs would face difficulties if the first payment – due on August 6 – was markedly lower than they had budgeted for.

It is expected ESPN will also maintain their commitment and will agree an additional deal that will include 10 Rangers matches this season.