Some may consider them to be impermissible based on the following verse in Surah Luqman:
“But there is the sort of person who pays for distracting tales, intending, without any knowledge, to lead others from God’s way, and to hold it up to ridicule.”
Those that use such verses say that these types blogs fall into the category of “distracting tales.”
The reply to this is that scholars differ on the meaning of “distracting tale”. There are those that say it means a drum; while others say it means music and listening to it; while others say it means polytheism. The strongest position is that it refers to those things which take people away from the path of God because the wording is general; and there is no evidence specifying it. This is the position of al-Imam at-Tabari.
Based on this, I find it very far-fetched for one to conclude that sport blogs fall in this category of those things which take one away from the path of God – completely or partially. This means that one would go astray if they participate in such things. The blogs usually consist of discussions ranging from teams’ performances and their activities, players, and other things related to sports. Furthermore, sport blogs were not meant initially to ridicule God or those things which are related to Him.
The only caution I offer is that the language between the bloggers and the ones commenting is clean not consisting of profanity and the like as this is not befitting of a Muslim. I also advise bloggers to be wary of mixing sports figures with religion (e.g., Tim Tebow) in a manner that would cause harm to Islam. Such possibilities would be to criticize someone for being a Christian and not because he is a terrible passer. Lastly, a Muslim must always remember that he or she must have a balanced approach to all things in his or her life.
Based on what I have presented, I find that such blogs are permissible. In fact, it may be a good change of pace for many of us constantly engrossed in work.
God knows best.