You can install https://chromewebstore.google.com/detail/close-tab/lnchemdcmhoccciihokpdkkekmnejfhj. Then, you can just right-click anywhere on a page and choose "Close tab".
After the extension is installed, goto the URL opera://extensions and turn on "Allow access to search page results" for the extension so it works on search engine pages and on pages you get to by clicking on links in search engine result pages.