Joining rows based on their timestamp

I’m building a simple message-board like app. For every topic there could be several posts, and I would like to present the topic in a list with some content from the latest post in that topic.
Simplifying it, say I have two tables:

Topics:

  • id (INT / AI )
  • subject (VARCHAR(150))
  • created (TIMESTAMP)

Posts:

  • id (INT / AI)
  • topic_id (INT / FK)
  • content (TEXT)
  • created (TIMESTAMP)

I want to retrieve rows from the Topics table, along with the latest row for each topic from the Posts table.
Can anyone suggest the most efficient way of accomplishing this (hopefully without a GROUP BY clause)?