Seo, who is 14-22 with a 4.90 ERA in 57 Major League appearances over the last three years, struggled to a no-decision against the Philadelphia Phillies' top farm club, the Scranton/Wilkes-Barre Red Barons.
Red Barons left fielder Mark Brudzinski reached Seo for long doubles and runs scored in both the first and third innings, while Seo also balked in a run in the second inning.
With Shane Victorino leading off third base, Seo inexplicably used his full, herky-jerky windup motion. The speedy centerfielder broke for home, Seo interrupted his motion for an illegal throw to catcher Mike DiFelice.
The damage could have perhaps been even more against Seo, but he was bailed out in the third inning when slow-footed right fielder Jim Rushford was gunned down by Luis Garcia stretching a single at second base.
Seo walked two and struck out two – including Phillies top prospect Ryan Howard – in a 59-pitch effort.
Garcia, a near-miss on the Mets' Opening Day roster, reached former Met Mike Bacsik for a three-run opposite field blast in the second inning.
Norfolk scored four times in the seventh off of Red Barons righthander Dan Giesi, plating runs on a Gerald Williams RBI triple, a two-run double off the right field wall by Brian Daubach and a Ron Calloway run-scoring single.