No Swat

Pedro Martinez started five games for the Mets in 2007, accumulated a total of 28 IP for the year, and didn't surrender a single home run all season.

Most Starts by a Met Pitcher in a Season in Which He Gave up 0 HRs:
Pedro Martinez 2007, 5 starts
Ron Darling 1983, 5 starts
Ed Lynch 1980, 4 starts

Pedro's 5 starts in a homer-free season is the most such starts in the majors since 1998, when John Halama of Seattle had 6 starts in a homer-free season. Going all the way back to 1900, the pitcher who had the most starts in a single season in which he gave up zero home runs was ... Babe Ruth! In 1916, the 21-year-old Babe had 41 starts, including 23 complete games, plus three relief appearances, for a total of 323 and two-thirds innings pitched, and surrendered not one home run all season. As a hitter he had 3 homers in 136 ABs that season. 1916 was certainly not a big year for home runs. That same season, Walter Johnson pitched even more innings than Ruth (38 starts, 36 complete games, 10 relief appearances and 369 and two-thirds innings altogether) and also allowed zero homers. All together there were 144 homers hit in the American League that season, a number topped by 10 of the 14 AL teams in 2007.

Since 1945, the most starts in a season by a pitcher who gave up no homers all season is 10 starts, by Vern Ruhle, former Mets pitching coach and recently deceased, who did it for the Astros in 1978 while throwing 68 innings, including the 10 starts plus three relief appearances. I would have thought that Ruhle was helped by pitching in the Astrodome, always a very tough place to hit homers, but in fact 8 of his 10 starts and 47 of his 68 total IPs that season were on the road.