Both dramas competing for first place ratings on Wednesdays and Thursdays feature singers turned actresses.

"My Spring Days" features Girls Generation singer Choi Sooyoung as a woman who gets a second chance at life after receiving a heart transplant. "My Lovable Girl" features f(x)'s Krystal Jung as a songwriter who gets a chance at realizing her dream thanks to the intervention of her late sister's boyfriend.

This week Sooyoung's drama "My Spring Days" held on to first place, while Krystal's followed in second.

"My Spring Days" reached 9.2 percent in the viewer ratings, which was only slightly down 0.1 percent from the 9.3 percent it got on Wednesday. The sweetly optimistic "Spring Days" also stars Kam Woo Sung and Lee Joon Hyuk as the brothers who both love Sooyoung's character Lee Bom Yi.

According to the Nielsen Ratings, the SBS drama "My Lovable Girl," dropped slightly in the ratings. It rated 7.8 percent on Wednesday but was only 7.3 percent on Thursday. The drama about a lost love and the darker side of the k-pop industry also stars Rain and Infinite's members L and Hoya. In this drama idols play idols and they don't necessarily always portray them in a positive way.

Both Choi Sooyoung and Krystal Jung have previous acting experience. Sooyoung had her first supporting role in the 2008 drama "Unstoppable Marriage," and after a series of cameos, took a leading role in "The Third Hospital." Her drama last role was playing matchmaker Gong Min Yong in the comedy "Dating Agency: Cyrano."

Krystal made her acting debut in 2010 with a supporting role in "More Charming By The Day." She had cameos and supporting roles in several dramas, the most notable of which was "The Heirs." In "The Heirs" she played Lee Bo Na, Lee Min Ho's ex-girlfriend. Lee Bo Na was a supporting role but a memorable one. Playing Yoon Se Na in "My Lovable Girl" is her first leading role.

Krystal Jung also contributed a song to the drama's soundtrack.

The third place drama "Iron Man," also called "Blade Man," does not feature any idols turned actors. That drama rose slightly, going from 5.5 percent in the viewer ratings to 6.9 percent on Thursday. "Iron Man" stars Lee Dong Wook as a man who sprouts blades from his skin when he becomes angry, and Shin Se Kyung as the warm-hearted woman who helps soothe his tortured soul.