Heilker is a physical 6-foot-2, 200-pounds with some mound presence. Heilker owns a mid-80s fastball, up to 88 mph. He throws a tight-spinning breaking ball and a playable changeup to round out his three-pitch mix. Heilker delivers from a high arm slot that generates a good downward plane, spin rate numbers on the fastball are high, ball jumps out of hand and gets on hitters quickly. As he continues to grow, Heilker shouldn’t be uncommitted for long as one of the sleeper arms in BC’s 2022 class that could make an impact at the next level. 

<blockquote class="twitter-tweet"><p lang="en" dir="ltr">Clips against Southeastern Iowa CC<br>3 innings 5ks 1H FB 86-87<br>2022 uncommitted <a href="https://twitter.com/BUncommitted?ref_src=twsrc%5Etfw">@BUncommitted</a> <a href="https://twitter.com/FlatgroundApp?ref_src=twsrc%5Etfw">@FlatgroundApp</a> <a href="https://twitter.com/NorthShoreTwins?ref_src=twsrc%5Etfw">@NorthShoreTwins</a> <a href="https://twitter.com/PBR_Uncommitted?ref_src=twsrc%5Etfw">@PBR_Uncommitted</a> <a href="https://twitter.com/PrepBaseballBC?ref_src=twsrc%5Etfw">@PrepBaseballBC</a> <a href="https://t.co/4FQd6oc07f">pic.twitter.com/4FQd6oc07f</a></p>&mdash; Willem Heilker (@w_heilker) <a href="https://twitter.com/w_heilker/status/1453429909464907776?ref_src=twsrc%5Etfw">October 27, 2021</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>