Ramirez followed up a header in the 24th minute against Wolves with a second goal 10 minutes after half-time to seal a 2-1 win that lifted Boro back to the top of the Championship.
Even though Wolves pulled a goal back in the final minute at the Riverside when Ben Gibson nodded into his own net, Middlesbrough boss Karanka thinks Ramirez's quality was there for all to see.
The Uruguayan, back in the side after being left out at Blackburn on Tuesday, has scored three times since arriving on loan from Southampton.
Karanka said: "We needed to win again
We had chances and two goals.
"Ramirez is getting better every game
I knew he was a good player at Southampton and from the Premier League.
"He knows the country and style, I knew he would be an important player
I thought it would take time but it has not taken long and he plays well sooner than I expected.
"But others have played well
I am pleased for a lot of them."
Karanka is not prepared to start thinking a Premier League return is on the cards, knowing Burnley can overtake Middlesbrough by beating Blackburn at Turf Moor on Saturday.
The Boro head coach said: "After January we are a better team than we were last season
One year more experience, more quality, better players.
"But always I think promotion is decided in the last few games
We only think of winning our games, not about promotion and where we are in the table.
"We won't win it easy, there are big games ahead
Hull, Burnley, Brighton, Derby are our rivals
We have eight games in a month so we have to stay motivated and ready to play."
Wolves dropped down a further place in the Championship after failing to build on last weekend's victory over Derby.
Kenny Jacket, the Wolves boss, said: "The top 10 of the Championship is a very high standard, a high standard of player
The likes of Middlesbrough have done very well to secure a high number of players here, very good quality players.
"When you look through the squad, you think who can play, and they have two players in every position of a similar ability.
"I felt Albert Adomah and George Friend down Boro's left and our right-hand side were dominant, very good, it opened the hole for Ramirez to come off the front
We never really got hold of that triangle.
"We finished quite strongly, got a goal back, but in the last few minutes we couldn't really get a run at a very strong defence."
Jackett added: "I was disappointed we weren't able to kick on from the weekend, but it is a tall order coming here and winning.
"The nature of the goals, the nature of the first goal, was a soft ball into the box and we let it bounce
It gave us a lot to do, you can't give soft goals away.
"We had a run towards the end but for all of our effort, we didn't have the player tonight that was going to go past his man."
Source : PA
Source: PA