It is quite hard to understand why the Shiv Sena chose to take on Sachin. Sachin's remark that "Mumbai belongs India" was most likely to be directed on the MNS and its chief. Perhaps he has not learned from what happened in 1999.
The Shiv Sena government established an award.... I think it's name is Maharashtra Bhushan Puraskar. Basically, Maharashtra's equivalent of the Bharat Ratna. The first recipient was, duh, PuLa. In his acceptance speech, PuLa made some remarks that were mildly critical of the Shiv Sena government. Nothing too hardcore, but a rebuke nonetheless.
Pu La Deshpande, the literary genius, a selfless and austere humanitarian, and an independent spirit, was (and continues to be after his death), something akin to a god for most Marathis. Bal Thackeray flipped his lid. He made some rude and uncharitable comments about PuLa, something like "jis thali mein khatey ho, usi mein chhed karte ho" (Source)
Shiv Sena had called for early state elections so that they could be held along with Lok Sabha elections and Shiv Sena could benefit from the NDA wave. The Saffron did win the Lok Sabha elections but lost the assembly elections. The election pundits were surprised and dumbfounded. One obvious reason was that the alliance between the two was well demarcated - BJP would be the senior partner in Lok Sabha hence fight more seats while vice-versa for Shiv Sena in Assembly Elections.
There has been absolutely no wonder that the MNS has not uttered a single word against Sachin. Raj Thakerey selectively picks his enemies. For instance, Mumbai-Pune circle accounts for 40% of film collections and hence he chose to attack Karan Johar's Wake Up Kid. He knew that the producer will buckle down due to commercial reasons. Likewise he has attacked Bachhans (a North India). He will not dare to attack an icon like Sachin.
Its just hard to understand how a seasoned politician like Bal Thakerey would commit such a rookie mistake. Even the BJP has distanced itself and has praised Sachin. The Sena on the other hand seems to be hell bent to isolate itself. It followed up its atack on Sachin which a physical attack on the IBN Lokmat.
In the recent Assembly elections, Shiv Sena was badly defeated. It was even forced to give up the post of the Leader of the Opposition as it won only 44 seats as against the BJP's 46. The BJP, marred by problems of its own chose to continue the Saffon alliance (its oldest ally) and let Shiv Sena fight many more seats. It surely could have won many more seats on its own.
The Congress on the other hand is following the model that the CPM employed so successfully in West Bengal - keep the alliance intact and divide the opposition. CPM continued to have an alliance with other Left Front members despite the fact that they enjoyed simple majority. For the moment, plan seems to be working, but its the poeple of Maharashtra who are suffering. Its Govt. is complacent because it knows it will be re-elected as the opposition is divided. Apart from some sugar coated statements from the Chief Minister, nothing has been done against the MNS.