The Blues were in a hurry to complete the move, while Rooney and Van Persie are back in full training and could return against Cardiff, and Man City's global expansion continues
Chelsea made three bids for Mohamed Salah in 24 hours to force through the Egyptian's signing in midweek.
The Londoners announced on Thursday they had agreed a deal with Swiss club Basel to capture Salah.
The Insider understands that an agreement was reached following a sustained period of bidding from Chelsea on Wednesday, with the Premier League club believed to have twice upped their offer before settling on a fee of £12.5 million plus £2m in add-ons.
Salah had also been the subject of an offer from Liverpool, but the Blues swiftly made their move after agreeing to sell Juan Mata to Manchester United on Wednesday for £37.1m.
Chelsea were keen to keep competition for places intense in the attacking midfield positions following the earlier sale of Kevin De Bruyne in the January window.
Salah will vie with Eden Hazard, Oscar, Willian and Andre Schurrle for a starting place at Stamford Bridge.
- Wayne Veysey
DAVID MOYES GIVEN BOOST OVER CROCKED FOURSOME
Manchester City's hopes for a four-trophy haul are still alive, but rivals United are on course for a quadruple of their own.
Boss David Moyes could receive a major injury booster ahead of the Red Devils' Premier League game against Cardiff City on Tuesday.
Rio Ferdinand, Marouane Fellaini, Robin van Persie and Wayne Rooney all resumed training with the first team during the last week and will be put through their paces on Monday morning.
Van Persie hinted to fans on Saturday that he would feature against Cardiff, tweeting "See you all on Tuesday" alongside a picture of Juan Mata, who had just touched down in his helicopter.
- Paul Clennam
MAN CITY'S GLOBAL EXPANSION CONTINUES
Manchester City plan to step up their search for partner clubs in other territories, with China and the Americas next on their hit list.
The Blues paid £11m earlier this week to buy an 80 per cent stake in Melbourne Heart, with the Australian side set to be renamed Melbourne City FC.
City paid £80m last summer to start up New York City FC and the Insider understands they are still on the lookout to expand the 'City Football Club' stable even wider.
Beijing and clubs in Mexico have also come under consideration.
City's owner Sheikh Mansour and the club's power brokers believe the moves are positioning the Manchester club to be one of the biggest in the world.
They have already overtaken the likes of Chelsea and Arsenal in the recent Deloitte rich list, despite the figures revealing the two London clubs charge much higher ticket prices.
- Paul Clennam