Where the first line kept its dragon submerged, the second brings it into view. Legge's translation gives the dragon appearing in the field, and states plainly that it will be advantageous to meet with the great man. The shift in imagery, from the hidden deep to open ground, marks the moment latent capacity becomes visible activity. The dragon is no longer merely present; it is now seen, and being seen changes what is required of it.
This line occupies the second place of the lower trigram Qian, a central position within that trigram and traditionally read as the place of a capable minister or an emerging figure who has not yet reached the highest office. The field itself is an image of the ordinary world rather than the sky the dragon will later command: open, level, shared ground where the dragon's power can be tested against other things and other people for the first time.
The advice to meet with the great man carries a double reading in the commentary tradition. The dragon in the field may itself be the great man others should seek, or it may still need a greater figure above it, a teacher or patron, to guide capacity newly made visible. Either reading agrees that visibility alone accomplishes nothing without relationship: strength shown in the field must find the right person to work beside, or the field becomes merely a stage with no one to watch it.