No one loves a small sample more than the Eyeball Scout, so let's make a bunch of sweeping conclusions based on 6 innings or less. Sean Nolin made his A's debut on Sunday afternoon and later in the game Ryan Dull made his 4th inning "1 IP appearance" out of the bullpen.
I'll be honest that I wasn't overly impressed with Nolin's debut (6 IP, 5 hits, 3 ER, 3 BB, 1 K), though one has to try to observe pitches in the context of nerves and adrenaline. There were certainly some positives and I'll start with those.
Nolin's over-the-top release appears to have some deception to the hitter. Mark Trumbo and Sean O'Malley swing very late on fastballs that hit only mid-to-high 80s on the radar gun, appearing not to see the ball immediately out of Nolin's hand.
I also liked the way Nolin cut the fastball in on the hands of right-handed batters, such as when he induced the DP ball off of Jesus Sucre's bat. Nolin's command of both sides of the plate with his fastball, along with what looks to be a solid changeup, will hold him in good stead.
Certainly Nolin is not lighting up the radar gun, topping out at 91MPH and sitting at 87-88MPH much of the afternoon. His command was spotty, most notably the tendency to lop-and-hang the curve, but based on his minor league track record I would presume this is likely to improve.
Where does that leave Nolin? With good command of an average fastball and a solid changeup, he would be a lot like Aaron Brooks from the left side. That would fall well short of Oakland's hopes for one of the key components of the Josh Donaldson trade.
In reality, Brooks and Nolin are not all that similar and the hope is that Nolin's other secondary pitches come along to make him more dynamic. That one pitch where he suddenly dropped down 3/4 to Logan Morrison was a great pitch and could be a weapon whether out of the rotation or the bullpen.
This start overall, however, did not particularly inspire my optimism even if the results were okay, and if you want to focus on "Hey, 6 IP, 3 ER" you also have to look at "3 BB, 1 K". Nolin didn't miss a lot of bats because his stuff didn't play better than "sometimes sneaky".
No doubt the results have been fantastic: 4 IP, 1 hit, 0 ER, 0 BB, 6K, and really Ryan Dull is just picking up where he left off in AA and AAA. However, it's Dull's first time through the league, so as you watch him fool batters you have to try to figure out "Is this sustainable, or is this the hitters' lack of familiarity with the pitcher?"
The arsenal itself is not necessarily that impressive. Dull's fastball sits in the low 90s and he is basically a "fastball/slider" pitcher. Dull relies on two key attributes for his success: he can spot his fastball and his slider is deceptive to the hitter.
Is that enough? The answer is: Yes, it can be. The reliever I keep flashing on, as I think of "absolute best case scenario" is Huston Street who, even as his fastball started topping out at 91MPH, was able to dominate consistently because of how deceptive his slider was (and still is).
Based on the hitters' reactions, clearly Dull releases his slider with the same arm angle and slot as he throws his fastball, and batters are not able to discern very quickly what pitch they are seeing. By the time they commit it's too late. Street can pretty much dominate by spotting his 90MPH fastball and locating his deceptive slider, and for at least 4 IP that's exactly what Dull has been able to do as well.
Do I think Dull is the next Street? No, probably not. The point is that the arsenal and the pitches themselves may be sufficient for Dull to be successful at the big league level. Now it's a question of consistency as well as whether batters can figure out a way to lay off the bad slider. So far they can't because they have to commit to their swing before they can pick up the slider. Unless or until that changes, Dull has a chance to be very successful.