Riding on Rayudu's undefeated knock of 118, Rest of India finished the fourth day's play at 296 for four taking their overall lead to a whopping 413 runs and have virtually put their hands on the trophy which they would be winning for 25th time.
With fate of the match virtually sealed, first innings centurion Suresh Raina is looking good for a second ton in the match and is batting on 40.
The only interest on fifth and final day will be whether national selectors recall Raina in the Test squad or try something out of the box by selecting Rayudu who has also scored a half century in the match.
Apart from that, Rayudu has had a good Ranji season for Baroda and also scored a century for India A against New Zealand.
The 27-year-old batsman also resurrected the Rest second innings as they were tottering at 69 for three at one stage. Rayudu added 140 runs for the fourth wicket with Manoj Tiwary, who hit a dogged 69.
During his 217 ball unbeaten knock, Rayudu has hit nine fours and four sixes --- all of them being straight lofts. This was his 14th century in first-class cricket.
Rest, began the day at 27 for 1, struggled for runs in the morning session with the Mumbai pace bowlers extracting a lot of movement.
Nightwatchman S Sreesanth (18) was run-out by a direct hit from cover point fielder Rohit Sharma. He responded to a call for a sharp single from partner M Vijay but was beaten by an agile throw from Rohit.