NEIL Harris said Ben Thompson's loan spell at Portsmouth helped him grow in "stature and confidence" as he outlined the midfielder's importance to Millwall for the rest of this season.
Thompson, 23, joined Pompey on a season-long loan last summer but was recalled this month, to the disappointment of boss Kenny Jackett and the south-coast club's fans.
Harris named Thompson on the bench against Blackburn before pitching him into action from the start against Middlesbrough last weekend.
Thompson expanded his skill set by featuring a number of times for Portsmouth as an attacking midfielder, and he was impressive as part of a central trio in Millwall's 4-3-3 formation at Boro.
After Thompson returned to his boyhood club Harris always intended to keep him for the season.
"It was always quite clear to me, we just had to be respectful with the whole situation," Harris said. "Ben's come back in from his loan at Portsmouth, he's grown in stature and confidence while he was there.
"Working with Kenny and Joe [Gallen, Portsmouth assistant manager] would have been a real benefit for him and playing week-in, week-out in a successful side was really important for him.
"We saw that in his performance at the weekend, I thought he was outstanding. Ben's future is here, I've talked many times about how important he is in the short term and long term.
"It's been a great experience for him but it was important that in the second half of the season we've got a squad of players that can compete and has quality as well.
"It's his importance around the training ground too, he's such a good personality, a very good pro for a young man and it's great to have him back."
Fred Onyedinma was also in the squad at Middlesbrough but a decision on whether he goes back out on loan is not likely to be made until later in the January window.
Harris said: "Fred really enjoyed himself at Wycombe in the first half of the season playing games regularly. He's been in nearly every match-day squad since I've been in charge the last four years. We forget he's still young.
"Fred has played for us and Wycombe this season so he can only play for us or go to Wycombe again. It's what we need and if Wycombe need him back.
"It was important to have Fred involved with us at the weekend because of the pace option. If he wasn't cup-tied he'd have had a really good chance of playing against Everton.
"Fred's come back, he's trained really well, it's been great having him back and the boys really like him. That competition for places is vital."
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