Can someone explain how this happens?

335275 (Main Chain)    2014-12-21 19:16:35    00000000000000000f4656f29e1e4a25d93ff9f8c7f87fe352979d707255d615
335276 (Main Chain)    2014-12-21 19:16:28    000000000000000009b568b45be21664352b90e1bc587f324009abcf9b51d11e

https://blockchain.info/blocks/1419167263187

It appears that block 335276 confirmed 7 seconds before the previous block. Is this just a matter of miner's clocks being out of sync?