Unfortunately that is Blossom End Rot. It doesn't have to be only on the bottom.

Thank you for the reply. Only the first tomato in the plant has this, all others seem to be growing fine. Would you still advice to take any measures?

In my experience tomatoes can develop blossom end rot at any point while they're growing, so I would definitely take steps to correct the problem ASAP. Since that is the first fruit for that plant, it was a bit more susceptible, but best not to take the risk of your entire crop ending up with BER.
You can buy sprays for your plant/fruit, but I would load your soil up with calcium first and foremost.

Check out the FAQ on Blossom End Rot (BER)

http://faq.gardenweb.com/faq/lists/cornucop/2000071437002250.html

Here is a link that might be useful: BER FAQ

If the scars are hard , then maybe, the tomato was chewed by some insect and the scars initiated. My guess is that if it was BER, you would've seen more tomatoes affected than just one. Additionally the presence of 2 separate scars says something. Another point is that YOU HAVE DESCRIBED THEM AS SCARS not rot.

Although the rot happens to be on the blossom side but it does not automatically mean BER. Not every rot is BER. The cause of BER is unique.

The bottom line is that you have a single bad fruit. as long as you dont get repeats that should not be a concern.

Thanks everyone for your input. I called them as scars because I have been watching them turn from small abrasions to their current state and they are not soft like a rot.

I will keep you guys posted about how things go for this plant.