@DAO and @Service beans clarification

I have a basic question. I've been reading through some tutorials about spring and hibernate integration and in most of them there are DAO and Service layers like below:

  public interface TeamDAO {

  public void addTeam(Team team);
   public void updateTeam(Team team);
  public Team getTeam(int id);
   public void deleteTeam(int id);
  public List<Team> getTeams();

 }

Then the implementation of the DAO is provided using the SessionFactory. For example:

 @Repository
 public class TeamDAOImpl implements TeamDAO {
        @Autowired
        private SessionFactory sessionFactory;

       //Implementation follows..
 }

And then there's another service interface the same as the DAO interface like below:

public interface TeamService {

 public void addTeam(Team team);
public void updateTeam(Team team);
public Team getTeam(int id);
public void deleteTeam(int id);
public List<Team> getTeams();

 }

And the service implementation:

 @Service
 @Transactional
 public class TeamServiceImpl implements TeamService {
   //HERE IS MY QUESTION
   @Autowired
   private TeamDAO teamDAO;

   //implementation follows
}

In the service implementation above where I marked "here is my question" I see that we inject only the interface TeamDAO which doesn't have the implementation of the TeamDAOImpl class. So how does the interface and its implementations get injected together in the service layer provided we only inject the interface TeamDAO and not TeamDAOImpl?