Only one other team had a less experienced starting rotation than this year's Oakland Athletics, and that was also an A's team from 2009. Kendall Graveman and Sean Manaea, joined by Cotton, Triggs, and Alcantara combine for only 92 games started and 559 innings pitched. Sonny Gray is expected to return in mid-April though, and has more experience than the five current starters combined, starting 96 games so far in his career and pitching 608 innings.
This season’s starting rotation for the Colorado Rockies has the fifth fewest prior games started with 145. After Tyler Chatwood (88 GS, 500 IP), their next most experienced starting pitcher would have been Chad Bettis (60 GS, 370.1 IP) who recently started chemotherapy, but will hopefully be able to return at some point this season.
Here are the teams since 2008 whose first five starting pitchers of the season had the most previous career starts: