The 22-year-old left training with the Chilean national side yesterday and headed to Europe for the final stage of transfer talks.
Man City are engaged in a three-way tussle with Man Utd and Barcelona for the player. United are considered the outsiders, having failed to budge from their £27 million offer, while Barca were widely expected to clinch the deal this week.
According to The Mirror, City made the £30 million offer yesterday in a last-minute bid to thwart Barca's chances. Sanchez is apparently unconvinced that Eastlands would be his best move but is "prepared to meet them in the next 24 hours".
Meanwhile, a spokesman for Udinese said: "Barcelona just have to iron out a few details but it's 80 per cent done."