The Boston Red Sox fell to the Pittsburgh Pirates 8-4 in Friday's series opener from PNC Park. Rookie left-hander Jake Bennett got the start and was roughed up by a Pittsburgh offense that has struggled in the month of August, allowing four runs on five hits, lasting only four innings and marking his fifth consecutive rough start. Is the 25-year-old beginning to hit the 'rookie wall' as he works his way through his first big league season? 

Bennett made his major league debut in early May, as the Boston rotation was ravaged by injuries; however, he was optioned back to Triple-A Worcester upon Sonny Gray's return from the injured list. He rejoined the Red Sox rotation on June 10, replacing starter Brayan Bello, who was sent to Worcester after a string of rough appearances. 

Upon his return to Boston, Bennett was more than up to the task, looking like one of the best rookie starters in baseball. In his first seven starts after being recalled, the left-hander allowed only nine earned runs on 47 hits in 43.1 innings while featuring pinpoint control, striking out 34 and walking only five. In that time, Bennett ranked in the top 10 among all qualified starters in ERA (1.87, 9th), walks per nine innings (1.03, 2nd) and fWAR (1.5, 3rd). 

However, in the five starts that have followed his incredible start, Bennett, who has well surpassed his professional career high of 75.1 innings pitched, has struggled mightily. In those five starts, Bennett has allowed 17 earned runs on 31 hits across 27 innings, good for a 5.67 ERA. Additionally, his pinpoint control has started to falter as he's issued eight walks while striking out 23. 

The heavy workload on both Bennett and fellow rookie left-hander Payton Tolle was a noted concern from Boston Chief Baseball Officer Craig Breslow ahead of the Aug. 3 trade deadline, as the third-year head of baseball operations noted they would have liked to add a starter in the days leading up to the deadline. However, the 6:00 p.m. deadline passed, and Breslow failed to add reinforcements to his taxed rotation. 

While the heavy workload has not caught up to Tolle yet, it appears that Bennett has begun to hit a wall in his first major league campaign. 

Up next for the Red Sox

Boston will look to even up the series with the Pirates and avoid the third consecutive series loss in game two of three from Pittsburgh on Saturday night. Sonny Gray (14-3, 2.79 ERA) will get the start for the Red Sox opposite Jared Jones (2-4, 5.03 ERA) for the Pirates. First pitch from PNC Park is set for 7:15 p.m. ET.