Masahiro Tanaka is still feeling discomfort in his pitching elbow despite not having picked up a baseball since receiving a platelet-rich plasma injection 10 days ago, according to Brian Cashman.

"He's improved, but he still feels it, although on a daily basis it decreases," Cashman told ESPN New York 98.7 FM's The Michael Kay Show. "So that's good but it's not good that he's still feeling it at this stage. So it's just day-by-day, week-by-week and we'll adjust accordingly. It's too early to call."

Tanaka was diagnosed with a partially-torn ulnar collateral ligament via MRI after complaining of elbow pain following a start against the Cleveland Indians on July 8.

In his first season as a Major Leaguer, Tanaka is 12-4 with a 2.51 ERA and 135 strikeouts in 129.1 innings.