Theming Drupal Lesson 6 Theming Views slideshow and jcarousel

Hello. Could you please help me solve a problem:

I'm trying to display a block in the teaser, but it doesn't show up, even though if I enter the line below in the full node, it works without any issues. Everything displays as it should. But I need it in the teaser.

<div class="field_image">   <? print render(module_invoke ('views' , 'block_view' , 'work_portfolio-block'));?></div>

Thank you in advance!